### 11th Standard CBSE Physics Study material & Free Online Practice Tests - View Model Question Papers with Solutions for Class 11 Session 2019 - 2020 CBSE [ Chapter , Marks , Book Back, Creative & Term Based Questions Papers - Syllabus, Study Materials, MCQ's Practice Tests etc..]

#### 11th CBSE Physics - Waves Five Marks Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

Two tuning forks A and B give 5 beats. A resounds with a closed column of air 15 cm long and B with an open column of ar 30.5 cm long. Caluculate their frequencies. Negelct and correction.

• 2)

A SONAR system fixed in a submarine operates at a frequency 40.0 KHz. An enemy submarine of 360 km/h. What is the frequency of sound reflected by the submarine? Take the speed of sound in water to be 1450 ${ ms }^{ -1 }$

• 3)

For the harmonic travelling wave  $y=2\cos { 2\pi } \left( 10t-0.0080x+3.5 \right)$ , where, x and y are in cm and t is in second. What is the phase difference between the oscillatory motion at two points separated by a distance of $\frac { \lambda }{2 }$.

• 4)

For the harmonic travelling wave $y=2\cos { 2\pi } \left( 10t-0.0080x+3.5 \right)$, where, x and y are in cm and t is in second. What is the phase difference between the oscillatory motion at two points separated by a distance of What is the phase difference between the oscillation of a particle located at x=100 cm, at t=Ts and t = 5s?

• 5)

Explain why (or how) bats can ascertain distance, directions, nature and sizes of the obstacles without any eyes?

#### 11th Standard CBSE Physics - Oscillation Five Marks Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A particle is subjected to two simple harmonic otions in the same direction having equal magnitude and equal frequency. If the resultant amplitude is equal to the amplitude of the individual motion. Fnd the phase difference between two individual motions.

• 2)

A particle moving with SHM ina stright line has a speed of 6 m/s when 4 m/s from the centre of oscillation and a speed of 8 m/s when 3 m from the oscillation and the shortest time taken by the partile in moving from the extreme position to a point mid way between the extreme position and the centre.

• 3)

A spring of force constant ${ 1200\quad Nm }^{ -1 }$is mounted on a horiontal table as a mass of 3 kg is attached to the free end of the spring, pulled sideways to adistance of 2.0 cm and released. What is
(i) the speed of the mass, if the spring in compressed?

• 4)

A spring of force constant ${ 1200\quad Nm }^{ -1 }$is mounted on a horiontal table as a mass of 3 kg is attached to the free end of the spring, pulled sideways to adistance of 2.0 cm and released. What is
(iii) total energy of the mass during oscillation?

• 5)

The motion of a particle executing simple harmonic motion is described by the displacement function.
x(t) = A cos (ωt + $\phi$)
If the initial (t = 0) position of the particle is I em and its initial velocity is ω cm/s, what are its amplitude and initial phase angle? The angular frequency of the particle is $\pi$s-1. If instead of the cosine junction, we choose the sine junction to describe the SHM: x = B sin (ພt + α), what are the amplitude and initial phase of the particle with the above initial conditions?

#### 11th Standard CBSE Physics - Kinetic Theory Five Marks Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A box of 1.00 m3 is filled with nitrogen at 1.5 atm at 300 K. The box has a hole of an area 0.010 mm2 . How much time is required for the pressure to reduce by 0.10 atm, if the pressure outside is 1 atm.

• 2)

Given below are densities of some solids and liquids.Give rough estimate of the size of their atoms.

 Substance Atomic Mass(u) Density (10-3 kgm-3) (i) Carbon(diamond) 12.01 2.22 (ii) Gold 197.00 19.32 (iii) Nitrogrn(liquid) 14.01 1.00 (iv) Lithium 6.94 0.53 (v) Fluorine(liquid) 19.00 1.14
• 3)

Given below are densities of some solids and liquids.Give rough estimate of the size of their atoms.

 Substance Atomic Mass(u) Density (10-3 kgm-3) (i) Carbon(diamond) 12.01 2.22 (ii) Gold 197.00 19.32 (iii) Nitrogrn(liquid) 14.01 1.00 (iv) Lithium 6.94 0.53 (v) Fluorine(liquid) 19.00 1.14
• 4)

Given below are densities of some solids and liquids.Give rough estimate of the size of their atoms.

 Substance Atomic Mass(u) Density (10-3 kgm-3) (i) Carbon(diamond) 12.01 2.22 (ii) Gold 197.00 19.32 (iii) Nitrogrn(liquid) 14.01 1.00 (iv) Lithium 6.94 0.53 (v) Fluorine(liquid) 19.00 1.14
• 5)

Given below are densities of some solids and liquids.Give rough estimate of the size of their atoms.

 Substance Atomic Mass(u) Density (10-3 kgm-3) (i) Carbon(diamond) 12.01 2.22 (ii) Gold 197.00 19.32 (iii) Nitrogrn(liquid) 14.01 1.00 (iv) Lithium 6.94 0.53 (v) Fluorine(liquid) 19.00 1.14

#### 11th CBSE Physics - Thermodynamics Five Marks Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A Carnot cycle is performed by 1 mole of air (r = 1.4) initially at 327o C. Each stage represents a compression or expansion in the ratio 1:6 Calculate the lowest temperature
Take R = 8.31 J/ mol-K

• 2)

A Carnot cycle is performed by 1 mole of air (r = 1.4) initially at 327o C. Each stage represents a compression or expansion in the ratio 1:6 Calculate network done during each side
Take R = 8.31 J/ mol-K

• 3)

A Carnot cycle is performed by 1 mole of air (r = 1.4) initially at 327o C. Each stage represents a compression or expansion in the ratio 1:6 Calculate efficiency of the engine
Take R = 8.31 J/ mol-K

• 4)

Two cylinders A and B of equal capacity are connected to each other via a stopcock. A contains a gas at standard temperature and pressure. B is completely evacuated. The entire system in thermally insulated. The stopcock is suddenly opened.
What is the change in internal energy of the gas?

• 5)

Two cylinders A and B of equal capacity are connected to each other via a stopcock. A contains a gas at standard temperature and pressure. B is completely evacuated. The entire system in thermally insulated. The stopcock is suddenly opened.
What is the change in temperature of the gas?

#### 11th Standard CBSE Physics - Thermal Properties of Matter Five Marks Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A circular disc made by iron is rotating about its axis of rotation with a uniform angular speed $\omega$
Determine the change in the linear speed of particle at the rim in percentage. The disc of rim is slowly heated from 20o C to 50o C keeping the angular speed uniform. Give that coefficient of linear expansion for the material of iron is  $1.2\times 10^{ -5\quad }$$^{0}$C-1

• 2)

A copper cube of mass 200 g slides down on a rough inclined plane having inclination 37o at a constant speed. If any loss in mechanical energy goes into the copper block as thermal energy. Find the increase in the temperature of the block as it slides down through 60 cm. Given, specific heat of copper is 420 J Kg-1K-1 .

• 3)

A brass wire 1.8 m long at 27o C is held taut with little tension between two rigid support. If the wire is cooled to a temperature of -39o C, what is the tension developed in the wire if its diameter is 2mm?

• 4)

The triple point of water is a standard fixed point in modern thermometry. Why? What is wrong in talking the melting point of ice and the boiling point of water as standard fixed points (as was originally done in the Celsius scale)?

• 5)

What is the temperature of the triple point of water on an absolute scale whose unit interval size is equal to that of the fahrenheit scale?

#### CBSE 11th Physics - Mechanical Properties of Fluids Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

The flow of blood in a larger artery of an anesthetised dog is diverted through a venturimeter. The wider part of the meter has a cross-sectional area equal to that of the artery, a1 = 8mm2. The narrow part has an area a2 = 4mm2. The pressure drop in the artery is 24 Pa. What is the speed of the blood in the artery?

• 2)

A fully loaded Boeing aircraft has a mass of 3.3$\times$105 kg. Its total wing area is 500 m2. It is in level flight with a speed of 960 km/h
(ii) Estimate the fractional increase in the speed of the air on the upper surface of the wing relative to the lower surface.[The density of air is $\rho$= 1.2 kgm-3

• 3)

Near the surface of the river, the velocity of water is 160 kmh -1 .Find the shearing stress between horizontal layers of waters, if the river is 6 m deep and the coefficient of viscosity of water is 10-2 poise.

• 4)

If 27 drops of rain were to be combine to form one new large spherical drop, then what should be the velocity of this large spherical drop? Consider the terminal velocity of 27 drops of equal size falling through the air is 0.20 ms-1

• 5)

The flow rate of water is 0.58 L/mm from a tap of diameter of 1.30 cm. After some times, the flow rate is increased to 4 L/min. Determine the nature of the flow for both the flow rates. The coefficient of visocity of water is 10-3 Pa-s and the density of water is 103 kg/m3.

#### CBSE 11th Physics - Thermal Properties of Matter Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

Perfect Black Body
Calculate the temperature (in K) at which perfect black body radiates energy at the rate of 5.67 W/cm2

• 2)

A Hot Body Radiating Energy
A hot body having the surface temperature 13270C. Determine the wavelength at which it radiates maximum energy. Given wien's constant = 2.9X10-3 mK.

• 3)

Aman went for a weekend trip with his parents and grandparents to a remote village. His grandfather showed him the fields and the crops they grow. As they moved forward, they saw that a bullock cart got struck in wet mud and the driver was not able to push it out by himself. Seeing him in distress, Aman ran to his help and together they pushed it out, but iron rim of the wheel came out.
They tried to put it on the wheel but it was smaller than diameter of wheel. Suddenly, he got an idea. He collected some wood and set them on fire and heated the rim and then rim easily slipped on the wheel. Cartman thanked Aman and moved away.
If the diameter of the rim and ring were 5.243 m and 5.231 m respectively at 27 $^{0}$C. To what temperature had Aman heated the ring so as to fit the rim of the wheel? Coefficient of linear expansion of iron = 1.20 x 10-5 K-1

• 4)

Radha was studying when she noticed her 2 years old younger brother was learning towards kitchen where her mother had kept the boiling water.
Radha ran towards him and caught him just as he was about to touch the boiling water. She moved him to the side and fell on the floor but she was happy that she saved her brother from getting burnt.
At atmospheric pressure, 2g of water having volume of 2.00 cm3 becomes 3342 cm3 of steam when boiled. The latent heat of vaporisation of water is 539 cal/g at 1 atm. What is the amount of heat added tot he system?

• 5)

What do you understand by thermal resistance?
closed cubical box is made of perfectly insulating material and the only way for heat to enter or leave the box is through two solid cylindrical metal plugs, each of cross-sectional area 12 cmand length 8 em fixed in the opposite walls of the box. The outer surface of one plug is kept at a temperature of 100°C while the outer surface of other plug is maintained at a temperature of 4°C. The thermal conductivity of the material of the plug is 2.0 W/m-°C. A source of energy generating 13 W is enclosed inside the box. Find the equilibrium temperature of the inner surface of the box assuming that it is the same at all points on the inner surface

#### CBSE 11th Physics -Thermodynamics Four and Six Marks Questions - by Girish - Chennai - View & Read

• 1)

Give an example of each of given below
Isochoric process

• 2)

Find the ratio of $\frac { \triangle Q }{ \triangle U } \quad and\quad \frac { \triangle Q }{ \triangle W }$ in an isobaric process. The ratio of molar specific heats, $\frac { C_{ p } }{ { C }_{ v } } =\gamma$ .

• 3)

1g of water at 1000C is converted into steam of the same temperature.If the volume of steam is 1551 cm3, find out the change in internal energy of the water.Latent heat of steam=$2256\times { 10 }^{ 3 }J/kg$ . Consider atm pressure.

• 4)

Consider  a Carnot cycle operating between T1=500K and T2=300K producing 1KJ of mechanical work pre cycle.Find the heat transferred to/by the engine by/to the reservoir.

• 5)

A refrigerator has to transfer an average of 263J of heat per second from temperature -100C to 250C.Calculate the average power consumed, assuming no energy losses in the process.

#### CBSE 11th Physics - Kinetic Theory Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

What is the average distance between atoms in water? Use the data given in examples 2 nd 3.

• 2)

Two non-reactive gases are kept in a container. The ratio of their partial pressures is given 5:3. Find the ratio of number of molecules.

• 3)

A gas at 270C in a cylinder has a volume of 4L and pressure 100 N/m2. If the gas is first compressed at constant temperature so that the pressure is 150 N/m2. Estimate the change in volume.

• 4)

A container is filled with a gas at a pressure of 76 cm of mercury at a certain temperature. The mass of a gas is increased by 50% by introducing more gas in the container at same temperature. Calculate the final pressure of the gas.

• 5)

If the mass of each molecule of a gas is halved and speed is doubled. Find the ratio of initial and final pressure.

#### CBSE 11th Physics - Waves Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

One morning, sameer went to the washroom for taking bath. He noticed that the pitch of sound produced went on increasing as he noticed that the pitch of sound produced went on increasing as he opened the tap to fill an empty bucket with water. He was surprise to observe that as the bucket started filling with water, the pitch of sound become higher. He shared this with his Physics teacher in the physics period. On getting a solution of problem from the teacher, sameer felt satisfied and expressed gratitude to the teacher.
(ii) When we start filling an empty bucket with water, the pitch of sound goes on increasing why?

• 2)

One day kapil had to go to his friend's house. He took hids mobile and headphone to listen to music while walking. On the way , he had to cross a railway line. He was so engrossed in the music that he did not hear the approaching train. Ttrain driver was blowing the horn but Kapil did not seeing this ran towards kapil and pushed him away just as train reached there. Kapil realised his mistake and thanked that person.
(ii) If a train emitting sound of frequency 500 Hz, is moving towards an observer with a speed of 30ms-1 then what is the frequency as heard by the listener?

• 3)

Shubham was good football player. but since last few dasy, he is suffering from stomach ache, could not attend and play matches. his parents took him to a doctor who examined and asked him to get an ultrasound done to detect the exact cause. Shubham was afraid of ultrasound scanner and refused to get it done. His parents made him understand that the scanner uses ultrasonic rays which go inside and detect any problem inside the body . So he got it done became fine again.
(ii) On which principle does the ultrasonic scanner work? If the ultrasound uses the operating frequency of 4.2 MHz, the speed of sound in the tissue is 1.7 kms-1. What is the wavelength of the sound in tissue?

• 4)

An aeroplane is going towards East at speed of ${ 510kmh }^{ -1 }$at a height of 2000 m. At a certain instant, the sound of the plane heard by a ground observer appears to come from a point vertically above him.
(iii) What values do you learn from this problem?

• 5)

Given below are some examples of wave motion. State n each case if the wave motion is transverse, longitudinal or a combination of both
(i) Motion of a kink in a longitudinal spring produced by displacing one end of the spring side ways
(ii) Waves produced in a cylinder containing a liquid by moving its piston back and forth
(iii) Waves produced by a motorboat sailing in water
(iv) Ultrasonic waves in air produced by a vibrating quartz crystal

#### CBSE 11th Physics - Mechanical Properties of Solids Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

A Cubical Body Gets Deformed
If the angle of shear is 30$^0$ for a cubical body and the change in length is 250 cm, then what must be the volume of this cubical body ?

• 2)

An Elongated Wire
If a wire of length 4 m and crosssectional area of 2m2 is stretched by a force of 3KN, then determine the change in length due to this force. Given Young's modulus of material of wire 110x109 N/m2.

• 3)

Elongation of Copper Wire
A copper wire is streched by 10 N force. If radius of wire decreases by 2%. How will Young's modulus of wire be affected?

• 4)

Volumetric Analysis
What will be the decrease in vloume of 100 cm3 of water under pressure of 100 atm if the compressibility of water is 4x10-5 per unit atmospheric pressure?

• 5)

Shear Modulus is Less than Young's Modulus
he shear modulus of a material is always considerably smaller than the Young's modulus for it. What does it signify?

#### CBSE 11th Physics - Oscillation Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

The physics teacher of class XI has assigned the work of finding the percentage change in the periodic time of a simple pendulum. Two students Rahul and Rohit made a theoretical study as well as verified experimentally whereas Rahul could not complete the work. When the teacher enquired the next day, Rohit could given the answer whereas Rahul could not
(c) Calculate the percentage change in the periodic time of a simple pendulum. If the mass of the bob be increased by 30%

• 2)

The potential energy of a particle of mass 1 kg in motion along the x-axis is given by U = 4 (1 - cos 2x) J Here x is in metres . Find the period of small oscillations.

• 3)

A body of mass m falls from a height h on to the pan of a spring balance. The masses of the pan and spring are negligible. The spring constant of the spring is k. Having stuck to the pan the body starts performing harmonic oscillations in the vertical direction. Find the amplitude and energy of oscillation.

• 4)

Two linear simple harmonic motions of equal amplitudes and frequencies ω and 2ω are impressed on a particle along the axes of X and Y respective/yo If the initial phase difference between them is π/2 find the resultant path followed by the particle.

• 5)

A particle is vibrating in SHM when the displacements of the particle from its equilibrium position are x1 and x2' it has velocities v1 and v2 respectively. Show that its time period is given by
$T=2\pi\sqrt{x_1^2-x_2^2\over v_2^2-v_1^2}$

#### CBSE 11th Physics -Gravitation Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

What will be the value of g at the bottom of sea 7 km deep?Diameter of the earth is 12800 km and g on the surface of the earth is 9.8 ms-2 .

• 2)

As you will learn in the text, a geostationary satellite orbits the earth at a height of nearby 36000 km from the surface of the earth.What is the potential due to the earth's gravity at the site of this satellite?(take the potential energy at infinity to be zero).MAss of the earth=$6.0\times { 10 }^{ 24 }$kg, radius=6400 km.

• 3)

An earth's satellite has a period of 90 min.Assuming the orbit to be circular, calculate its height.Take radius of the earth equal to 6380 km and g at the surface of the earth equal 9.8m/s2 .

• 4)

Shweta was reading a book on the biography of Issac Newton. She read that Newton was sitting under an apple tree when a falling apple led him to develop a whole new science of gravity. After reading the book, shweta realised that every phenomenon in universe has some scientific fact associated with it, it depends on us whether we look for a scientific fact or associate a superstition with it.
How can you find the mass of the earth using law of gravitation?

• 5)

Arjun was a student of class IX. He was sitting in a garden along with his grandmother, who was a retired physics teacher. Suddenly he saw an orange falling from the tree. Immediately he asked his grandmother that both of the orange and earth experience equal and opposite forces of gravitation, then why it is the orange that falls towards the earth and not the earth towards the orange. His grandmother explained him the reason in a simple way.
(i)What are the values being displayed by Arjun?
(ii)What in your opinion may be the reason for this observation?

#### CBSE 11th Physics -System of Particles and Rotational Motion Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

Two bodies of masses 1 kg and 2 kg are located at (1, 2) and (-1, 3), respectively. Calculate the coordinates of the centre of mass.

• 2)

Centre of gravity of a body on the earth coincides with its centre of mass for a small object and for a large object, it may not.
What is the qualiative meaning of small and large in this regards? For which following two of them coincides, a building, a pond, a lake, a mountain.

• 3)

The angular speed of a motor wheel is increased from 1200 rpm to 3120 rpm in 16s.
What is its angular acceleration, assuming the acceleration to be uniform?

• 4)

To maintain a rotor at a uniform angular speed of 200 rads-1 , an engine needs to transmit a torque of 180 N-m. What is the power required by engine? Assume 100% efficiency of engine.

• 5)

Since his childhood Sanjay had always seen his mother grinding flour in the grindstone. He had observed that his mother had to do a lot of hand work in order to get flour from wheat. He felt very helpless at that time. As he grew older he thought of an idea to connect an electric motor to the wheel of grindstone . Now, it become very easy to get flour with help of grindstone and now his mother is very happy and felt proud of his intelligence.
A grinding stone of diameter 4 m revolving at 120 rpm accelerates to 660 rpm in 9s. Calculate the angular acceleration and linear acceleration.

#### CBSE 11th Physics - Work, Energy and Power Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

The nucleus Fe27 emits a $\gamma$-ray of energy 14.4 keV. If the mass of the nucleus is 56.935 amu, calculate the recoil energy of the nucleus.

• 2)

One day Pawan went to super market to purchase some groceries. There he saw an old lady struggling with her shopping. He immediately showed her the lift and explained to her how she can carry her goods from one floor to the other. Even then the old lady showed hesitation to use the lift. On seeing this, Pawan took the lady into the lift and showed her how to operate the lift. The old lady was very happy and easily finished her shopping.
(ii) An elevator which can carry a maximum load of 1800 of 2m/s. The frictional force opposing he motion is 4000 N.Determine the maximum power delivered by the motor to the elevator in horse power

• 3)

Rocket Propulsion
A toy rocket of mass 0.1 kg has a small fuel of mass 0.02 kg which it burns out in 3 s. Starting from rest on horizontal smooth track it gets a speed of 20 ms-1 after the fuel is burnt out. What is the approximate thrust of the rocket ? What is the energy content per unit mass of the fuel ? (Ignore the small mass variation of the rocket of the rocket during fuel burning).

• 4)

When a pebble Hits the Ground
Consider a drop of small pebble of mass 1.00 g falling from a cliff of height 1.00 km. It hits the ground with a speed of 50.0 ms-1. What is the work done by the unknown resistive force ?

• 5)

A railway carriage of mass 9000kg moving with a speed of 36km/h collides with stationary carriage of the same mass. After the collision, the carriage get coupled of the same mass. After the collision, the carriage get coupled and move together. What is their common speed after collision? what type of collision is this?

#### 11th Standard CBSE Physics - Laws of Motion Four and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

A cyclist speeding at 18km/h on a level road takes a sharp circular turn of radius 3m without reducing the speed. The coefficient of static friction between the tyres and the road is 0.1.will the cyclist slip while taking the turn?

• 2)

A circular race track of radius 300m is banked at angle of 15o . IF the coefficient of friction between the wheels of  a race car and the road is 0.2, what is the (i)optimum speed of the race to avoid wear and tear on its tyres and (ii) maximum permissible speed to avoid slipping?
$\left[ tan{ 15 }^{ o }=0.2679 \right]$

• 3)

The radius of curvature of  a railway track at a place, where the train is moving at  a speed of 72kmh-1 is 625m. The distance between the rails is 1.5m. Find the angle and the elevation of the out rails so that there may be no side pressure on the rails. Take, g=9.8 ${ m }/{ { { s }^{ 2 } } }$
$\left[ { tan }^{ -1 }(0.00653)=3.7{ 4 }^{ o },sin3.7{ 4 }^{ o }=0.06522 \right]$

• 4)

A girl riding a bicycle along a straight road with a speed of 5 m/ s throws a stone of mass 0.5 kg which has a speed of 15 m /s with respect to the ground along her direction of motion. The mass of the girl and bicycle is 50 kg. Does the speed of the bicycle change after the stone is thrown ? What is the change in speed, if so ?

• 5)

Vipul was driving on the road with his old grandmother. She was sitting on the front seat with him. When vipul was about to reach his destination, he stopped the engine and did not apply the brakes. Even then the car was running on the road for sometimes.
His grandmother surprised and asked her grandson the reason the car running without the engine on. Vipul was the student of science studying in class XIth. He explained his grandmother that it is only the momentum due to which the car is going on.
(i) What values Vipul exhibit here ?
(ii) What is momentum and on which factor it depends ?

#### CBSE 11th Standard Physics - Mechanical Properties of Fluids Five Mark Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

The reading of pressure meter attached with a closed pipe is $3.5\times { 10 }^{ 5 }Nm^{ -2 }$  . On opening the valve of the pipe, the reading of the pressure meter is reduced to $3.0\times { 10 }^{ 5 }Nm^{ -2 }$ . Calculate the speed of the water flowing in pipe.

• 2)

A liquid is kept in cylindrical vessel which is rotated along its axis. The liquid rises at the sides. If the radius of vessel is 0.05 m and the speed of rotation is 2 rev/s, find the difference in height of the liquid at the centre of the vessel and its sides.

• 3)

Explain why?
To keep a piece of paper horizontal, you should blow over, not under it.
According to Bernoulli's theorem, for horizontal flow of fluids,
$\left( p+\frac { 1 }{ 2 } \rho { v }^{ 2 }=constant \right)$
Therefore, when velocity of fluid increases, its pressure decreases and vice-versa.

• 4)

Explain why?
A fluid flowing out of small hole in vessel results in a backward thrust on the vessel.
According to Bernoulli's theorem, for horizontal flow of fluids,
$\left( p+\frac { 1 }{ 2 } \rho { v }^{ 2 }=constant \right)$
Therefore, when velocity of fluid increases, its pressure decreases and vice-versa.

• 5)

Mercury has an angle of contact equal to 1400 with soda lime glass. A narrow tube of radius 1.00 mm made of this glass is dipped in a trough containing mercury . By what amount dos the mercury dip down in the tube relative to the liquid surface outside? Surface tension of mercury at the temperature of th experiment is 0.456 N/m .Density of mercury? =13.6$\times$103 kg/m3

#### 11th CBSE Physics - Mechanical Properties of Solids Five Mark Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

What is the length of a wire that breaks under its own weight when suspended vertically? Breaking stress=5x107 Nm-2 and density of the material of the wire=3x103 kg/m3

• 2)

Two wires of equal cross-section but one made of steel and the other copper are joined end to end. When the combination is kept under tension, the elongation in the two wires is found to be equal. Given Young's moduli of steel and copper are 2.0x1011 Nm-2 and 1.1x1011Nm-2 Find the ratio between the lengths of steel and copper wires

• 3)

The edge of an aluminium cube is 10 cm long.One face of the cube is firmly fixed to a vertical wall.Amass of 100 kg is then attached to the  opposite face of the cube.
The shear modulus of aluminium is 25 GPa.What is the vertical deflection of this face?

• 4)

A14.5kg mass, fastened to one end of a steel wire of unstretched length 1m is whirled in a vertical circle with an angular frequency of 2 rev/s at the bottom ofthe circle. The cross-sectional area of the wire is 0.065 cm2.Calculate the elongation of the wire when the mass is at the lowest point of its path.

• 5)

Four identical hollow cylindrical columns of mild steel support a big structure of mass 50,000 kg. The inner and outer radii of each column are 30 cm and 60 cm respectively. Assuming the load distribution to be uniform, calculate the compressional strain of each column. Young's modulus, $\Upsilon$ = 2.0 x 1011 Pa.

#### CBSE 11th Standard Physics - Gravitation Five Mark Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A spaceship is launched into a circular orbit close to the surface of the earth. What additional velocity has now to be imparted to the spaceship in the orbit to overcome the gravitational pull.

• 2)

Consider two solid uniform spherical object of the same density $\rho$ . One has a radius R and the other a radius 2R. They are in outer space where the gravitational field from other objects are negligible. If they are at rest with their surfaces touching, then what is the contact force between the objects due to their gravitational attraction?

• 3)

Choose the correct alternatives.
Acceleration due to gravity increases/decreases with increasing depth(assume the earth to be a sphere of uniform density).

• 4)

The planet Neptune travels around the sun with a period of 165 yr. Show that the radius of its orbit is approximately thirty times that of the earth's orbit, both being considered as circular.

• 5)

A particle is fired vertically upwards with a speed of 15 km/s. Find the speed of particle when it goes out of the earth's gravitational pull.

#### 11th CBSE Physics - System of Particles and Rotational Motion Five Mark Model Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

In given pulley mass system, mass m1 = 500 g, m2 = 460 g and the pulley has a radius of 5 cm. When released from rest, heavier mass falls through 7.50 cm in 5 s. There is no slippage between pulley and string.
What is magnitude of acceleration of mass?

• 2)

Find the centre of mass for a solid cone of base radius r and height h.

• 3)

A man stands on a rotating platform with his arms stretched horizontally holding a 5 kg weight in each hand. The angular speed of the platform in 30 rpm. The man then brings his arms close to his body with the distance of each weight from the axis changing from 90 cm to 20 cm. The moment of inertia of the man together with the platform may be taken to be constant and equal to 7.6 kg-m2.
Is kinetic energy conserved in the process? If not, from where does the change come about?

• 4)

A disc of radius R is rotating with an angular speed $\omega$ , about a horizontal axis. It is placed on a horizontal table. The coefficient of kinetic friction is ${ \mu }_{ k }$.
What happens to the linear velocity of a point on its rim when placed in contact with the table?

• 5)

A disc of radius R is rotating with an angular speed $\omega$ , about a horizontal axis. It is placed on a horizontal table. The coefficient of kinetic friction is ${ \mu }_{ k }$.
Calculate the time taken for the rolling to begin.

#### CBSE 11th Physics - Motion in a Plane Four Marks and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

Resultant velocity of a Boat
A motor boat is racing towards North at 25km/h and the water current in that region is 10 km/h in the direction of 600 East to South. Find the resultant velocity of the boat.

• 2)

A soccer player kicks a ball at an angle of ${ 30 }^{ \circ }$with an initial speed of 20m/s. Assuming that the ball travels in a vertical plane.Calculate the maximum height reached$g=10m/s^{ 2 }$

• 3)

A cricket ball us thrown at a speed of 28${ ms }^{ -1 }$in a direction ${ 30 }^{ \circ }$above the horizontal. Calculate the maximum height

• 4)

A body of mass 10 kg revolves in a circle of diameter 0.4m making 1000 revolutions per minute. Calculate its linear velocity and centripetal acceleration.

• 5)

From a school, a group of boys went for a picnic in a village. They went through fields and enjoyed the beauty of nature. While walking, they saw a well which they had never seen in the city. They were very excited and started drawing water from well. They planned to have a competition in which they decide that the who would draw more water would become winner . A villager who was listening to them, went to them and told them about the importance of water. He also explained that they use the water of this for irrigating their fields and also for drinking.
If the two boys raising the bucket, pull it an angle $\theta$ to each other and each exerts a force of 20N, their effective pull is 30N. What is the angle between their arms?

#### CBSE 11th Physics - Motion in a Straight Line Four Marks and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

A train 100 m long is moving with a speed of 60 km/h. In what time shall it cross a bridge of 1 km long?

• 2)

During a hard sneeze, your eyes might shut for 0.5 s. If you are driving a car at 90 km/h during such a sneeze, how far does the car move during that time?

• 3)

If the average speed of the particle is [ ${ 2t }^{ 2 }\hat { i } +3t\hat { j }$ ], then find out the instantaneous speed of the particle.

• 4)

Prove Galileo's Law of Odd Numbers

• 5)

Shruti goes to school with his brother Alok in their own car.The school is about 10km apart from their home.They drive on alternate days.Alok is a very careful driver but Shruti drives rashly.She takes 3 min less than Alok in reaching the school.Alok advices Shruti to drive safely but she hardly listens.
What is the difference between average speeds of Shruthi and Alok if later takes 15 min to drive to the school?

#### 11th Standard CBSE Physics - Units and Measurements Four Marks and Five Marks Questions - by Girish - Chennai - View & Read

• 1)

The sun's angular diameter is measured to be 1920. The distance r of the sun from the earth is $1.496\times { 10 }^{ 11 }$ m. What is the diameter of the sun?

• 2)

Write down the number of significant figure in the following.
0.060

• 3)

A drop of olive oil of radius 0.25 mm spreads into a circular film of radius 10 cm on the water surface. Estimate the molecular size of olive oil.

• 4)

The refractive index of water is found to have the values 1.29,1.33,1.34,1.35,1.32,1.36,1.30 and 1.33.Calculate mean absolute error

• 5)

The refractive index of water is found to have the values 1.29,1.33,1.34,1.35,1.32,1.36,1.30 and 1.33.Calculate fractional error

#### 11th Standard CBSE Physics - Waves Three Marks Questions - by Girish - Chennai - View & Read

• 1)

A guitar string is 90 cm long and has a fundamental frequency of 124 H. Where should it be pressed to produce a fundamental frequency of 180 Hz?

• 2)

A standing wave is formed by two harmonic waves, ${ Y }_{ 1 }=Asin(kx-\varpi t)$and ${ Y }_{ 2 }=Asin(kx-\varpi t)$travelling on a string in opposite directioons. Mass density of the string is $\rho$ and area of cross-section is s. Find the total mechanical energy between two adjacent nodes on the string.

• 3)

A train, standing at the outer signal of a railway station blows a whistle of frequency 400 Hz in still air. What is the speed of sound in each case? The speed of sound in still air can be taken as 340ms-1.

• 4)

One end of a long string of linear mass density 8.0X10-3 kg m-1 is connected to an electrically driven tuning fork of frequency 256 Hz. The other end passes over a pulley and is tied to a pan containing a mass of 90kg. The pulley end absorbs all the incoming energy so that reflected waves at the end have negligible amplitude. At t=0, the left and (fork end) of the string  x = 0 has zero transverse displacement (y=0) and is moving along positive y-direction. The amplitude of the wave is 5.0 cm. Write down the transverse displacement y as function of x and t that describes the wave on the string

• 5)

A transverse harmonic wave on a string is described by y(x, t)=3.0sin (36t+0.018x+$\pi /4$) Where, x and y are in cm and t in seconds. The positive direction of x is from left to right
What is the initial phase at the origin?

#### 11th Standard CBSE Physics - Oscillation Three Marks Questions - by Girish - Chennai - View & Read

• 1)

A bodyoscillates with SHM according to the equation x(t) $=5cos\left( 2\pi t+\frac { \pi }{ 4 } \right)$ , where x is in metres and t is in seconds.
Calculate the following
magnitude of maximum velocity

• 2)

When the mass is displaced a little to one side, one spring gets compressed and another is elongated.Due to which the combination of sp[rings. Here, effective spring factor k will be given by $k={ k }_{ 1 }+{ k }_{ 2 }=600+600=1200{ Nm }^{ -1 }$

• 3)

Answer the following questions
The motion of a simple pendulum is approximately simple harmonic for small angle oscillations. For larger angles of oscillation, a more involved analysis sjows that T is greater than $2\pi \sqrt { \frac { l }{ g } }$ .Think of a qualitative argument to appreciate this result.

• 4)

In the previous question, let us take the position of mass when the spring is unstretched as x=0 and the direction from left to right as the positive direction of the x-axis. Given x as a function of time t for the oscillating mass, if at the moment we start the stopwatch (t=0), the mass is
at the maximum stretched position.
In what way do these functions for SHM differ from each other, in frequency, in amplitude or the initial phase?

• 5)

A body weighing 10 g has a velocity of 6 cms after one second of its starting from mean position. If the time period is 6 s, then find the kinetic energy, potential energy and the total energy.

#### 11th Standard CBSE Physics - Kinetic Theory Three Marks Questions - by Girish - Chennai - View & Read

• 1)

Write the difference between ideal gas and real gas.

• 2)

If one mole of a monoatomic gas is mixed with three moles of a diatomic gas.What is the molar specific heat of mixture at constant value?[Take, R=8.31 J mol-1K-1]

• 3)

A cylinder of fixed capacity contains 44.8 L of helium gas at STP.Calculate the amount of heat required to raise the temperature of container by 150 C?[given R=8.31 J mol-1K-1]

• 4)

A gaseous mixture contain 16 g of helium and 16g of oxygen, then calculate the ratio of Cp/CV of the mixture.

• 5)

What will be the mean free path of nitrogen gas at STP of given diameter of nitrogen molecule =2$\overset { 0 }{ A }$ ?

#### 11th Standard CBSE Physics - Thermodynamics Three Marks Questions - by Girish - Chennai - View & Read

• 1)

An ideal Carnot engine takes heat from a sources at 317o C, does some external work and delivers the remaining energy to a heat sink at 117o C. If 500 Kcal of heat is taken from the sources.
How much heat is delivered to the sink?

• 2)

A monoatomic ideal gas$(\gamma =\frac { 5 }{ 3 } )$initialy at 170C is suddenly compressed to one-eight of its original volume.
Find the final temperature after compression.

• 3)

Explain, why?
(ii) The coolant in a chemical or a nuclear plant, i.e. the liquid used to prevent the different parts of a plant from getting too hot should
have high specific heat.

• 4)

Explain, why?
(iv) The climate of a harbor town is more temperate than that of a town in a desert at the same latitude

• 5)

In changing the state of a gas adiabatically from an equilibrium state A to another equilibrium state B, an amount of work equal to 22.3 J is done on the system. If the gas is taken from state A to B via a process in which the net heat absorbed by the system is 9.35 cal, how much is the net work done by the system in the latter
case? (Take 1 cal = 4.19 J).

#### 11th Standard CBSE Physics - Thermal Properties of Matter Three Marks Questions - by Girish - Chennai - View & Read

• 1)

At what temperature, if any, do the following pairs of scales gives the same reading?
Fahrenheit and Kelvin.

• 2)

A box having total surface area 0.05 m2 and of 6 mm thick side walls is filled with melting ice and kept in room. Calculate the thermal conductivity of the box material if 0.5 kg of ice melts in 1 h. The room temperature is 40o C and latent heat of fusion of ice = $3.33\times { 10 }^{ 5 }J{ kg }^{ -1 }$

• 3)

Explain the following
Hot tea cools rapidly when poured into the saucer from the cup.

• 4)

A fat man is used to consuming about 3000 kcal worth of food every day. His food contains 50g of butter plus a plate of sweets every day, besides items which provide him with other nutrients (proteins, vitamins, minerals, etc) in addition to fats and carbohydrates. The calorific value of 10g of butter is 60kcal and that of a plate of sweets is of average 700kcal per day? Assume the man cannot resist eating the full plate of sweets once it is offered to him.

• 5)

A metallic ball has a radius of 9.0 cm at 00C. Calculate the change in its volume when it is heated to 900 C. Given the coefficient of linear expansion of metal of ball is 1.2x10-5 K.

#### 11th Standard CBSE Physics - Mechanical Properties of Fluids Three Marks Questions - by Girish - Chennai - View & Read

• 1)

27 identical drops of water are falling down vertically in air each with a terminal velocity 0.15$ms^{ -1 }$>if they combine to form a single bigger drop, what will be its terminal velocity?

• 2)

Two soap bubbles have radii in the ratio2:3.Compare the excess of pressure inside these bubbles.

• 3)

What is the largest average velocity of blood flow in an artery of radius 2 $\times$ 10- 3m, if the flow must remain laminar?

• 4)

What is the corresponding flow rate? (Take viscosity of blood to be 2.084$\times$ 10- 3Pa-s)

• 5)

Show that ifn equal rain droplets falling through air with equal steady velocity ono cms-1 coalesce, the resultant drop attains a new terminal velocity ono n2/3cms- 1.

#### 11th Standard CBSE Physics - Mechanical Properties of Solids Three Marks Questions - by Girish - Chennai - View & Read

• 1)

Two parallel steel wires A and B are fixed to rigid support at the upper ends and subjected to the same load at the lower ands. The lengths of wires are in the ratio 4:5 and their radii are in the ratio 4:3. The increase in the length of the wire A is 1mm. Calculate the increase in the length of the wire B.

• 2)

Determine the volume contraction of a solid copper cube, 10cm on an edge, when subjected to a hydraulic pressure of 7x106 Pa. Bulk modulus for copper=140x109 Pa.

• 3)

Read the following two statements below carefully and state, with reasons, if it is true or false.
(a) The Young's modulus of rubber is greater than that of steel;
(b) The stretching of a coil is determined by its shear modulus.

• 4)

A steel wire of length 4 m is stretched through 2 mm. The cross-section area of the wire is 2.0 mm2. If Young's modulus of steel is 2.0 x 1011 N/m2, find (i) the energy density of the wire and (ii) the elastic potential energy stored in the wire.

• 5)

Explain why steel is more elastic than rubber.

#### 11th Standard CBSE Physics - Gravitation Three Marks Questions - by Girish - Chennai - View & Read

• 1)

An artificial satellite is going round the earth, close to the surface. What is the time taken by it to complete one round?

• 2)

The distances of two planets from the sun are 1013 m and 1012 m, respectively. Calculate the ratio of time period and the speeds of the two planets

• 3)

If the earth is 1/4 of its present distance from the sun, then what is the duration of he year?

• 4)

The mass of a spaceship is 1000 kg. It is to be launched from the earth's surface out into free space. The value of g and R(radius of earth) are 10${ m }/{ { s }^{ 2 } }$and 6400km, respectively.What is the required energy for this work done?

• 5)

What will be the potential energy of a body of mass 67kg at a distance of $6.6{ \times 10 }^{ 10 }m$from the centre of the earth? Find gravitational potential at this distance.

#### 11th Standard CBSE Physics - System of Particles and Rotational Motion Three Marks Questions - by Girish - Chennai - View & Read

• 1)

A solid cylinder of mass 20 kg rotates about its axis with angular speed of (100 rad/s). The radius of cylinder is 0.25m. What is the kinetic energy of rotation of cylinder? What is the magnitude of angular momentum of the cylinder about its axis?

• 2)

A bullet of mass 10 g and speed 500 m/s is fired into a door and gets embedded exactly at the centre of the door. The door is 1.0 m wide and weight 12 kg. It is hinged at one end and rotates about a vertical axis practically without friction. Find the angular speed of the door just after the bullet embeds into it.

• 3)

A cylinder of mass 10 kg and radius 15 cm is rolling perfectly on a plane of inclination ${ 30 }^{ \circ }$. The coefficient of static friction, ${ \mu }_{ s }=0.25$.
How much is the force of friction acting on the cylinder?

• 4)

A particle on a rotating disc have initial and final angular position are -2rad, +6rad. In which case, particle undergoes a negative displacement.

• 5)

A particle on a rotating disc have initial and final angular position are -4rad, -8rad. In which case, particle undergoes a negative displacement.

#### 11th Standard CBSE Physics - Work, Energy and Power Three Marks Questions - by Girish - Chennai - View & Read

• 1)

The blades of windmill sweep out a circle of area A.
(i) If the wind flows at a velocity v perpendicular to the circle, what is the mass of the air passing through it in time t?

• 2)

The blades of windmill sweep out a circle of area A.
(ii) What is the kinetic energy of the air?

• 3)

Under the correct alternative.
Whan a conservation force does positive work on a body, the potential energy of the body increase decrease/remains unaltered.

• 4)

Work done by a body against friction always results in a loss of its kinetic/potential energy

• 5)

The rate of change of total momentum of a many particle systems is proportional to the external force/sum of the internal forces on the system.

#### 11th CBSE Physics - Laws of Motion Five Mark Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A hammer weighing 1 kg moving with the speed of 20 m / s strikes the head of a nail driving it 20 cm into a wall. Neglecting the mass of the nail, calculate
(i) the acceleration during the impact
(ii) the time interval during the impact
(iii) the impulse.

• 2)

A hammer weighing 1 kg moving with the speed of 20 m / s strikes the head of a nail driving it 20 cm into a wall. Neglecting the mass of the nail, calculate
(iii)  the impulse.

• 3)

Give the magnitude and direction of the net force acting on
(ii) a cork of mass 10 g floating on water.

• 4)

Give the magnitude and direction of the net force acting on
(iii)  a kite skillfully  held stationary in the sky.

• 5)

A circular motion addict of mass 80 kg rides a Ferris wheel around in a vertical circle of radius 10m at a constant speed of 6.1 m/s.
(ii) the highest point of the circular path

#### 11th CBSE Physics - Work, Energy and Power Five Mark Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

A stone of mass 0.4 kg is thrown vertically upward wit a speed of 9.4 m/s/ Find the potential and kinetic energies after half second?

• 2)

A running man has half the kinetic energy that a boy of his mass has. the man speeds up by 1.0 m/s and then same energy as the boy. what were the original speeds of the man and the boy?

• 3)

State if each of the following staement is true or false. Give reasons for your answer.
(ii) Total energy of a system is always conserved, no matter what internal and external forces on the body are present?

• 4)

Answer carefully with reasons
(i) In an elastic collision of two billiard balls, is the total kinetic energy conserved during the short time of collision of the balls i.e. when they are in contact?

• 5)

Answer carefully with reasons
(iv) If the potential energy of two billiard balls depends only on the separation distance between their centres, is the collison elastic or inelastic?

#### 11th CBSE Physics - Motion in a Plane Five Mark Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

State the reason , whether the following algebraic operations with scalar and vector physical quantities are meaningful
Adding a scalar to a vector of dimensions

• 2)

State the reason , whether the following algebraic operations with scalar and vector physical quantities are meaningful
Adding any two vectors

• 3)

State the reason , whether the following algebraic operations with scalar and vector physical quantities are meaningful

• 4)

If A and B are two vectors such that $\left| A\times B \right| =\sqrt { 3 } A.A$ Then,
Also, find the value of  $\left| A\times B \right|$

• 5)

A ball rolls of the top of a stairway with horizontal velocity of 1.8 m/s. The steps are 0.24 m high and 0.2 m wide. Which step will the ball hit first? Take g=9.8 m/s2

#### CBSE 11th Standard Physics - Motion in a Straight Line Five Mark Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

Two parallel rail tracks run North-South.Train A moves North with a speed of 54 kmh-1. and train B moves South with a speed of 90 kmh-1. What is the
relative velocity of ground with respect to B?

• 2)

(i)Draw position-time graph for
(a) Accelerated motion  (b) Retarded motion
(ii)A juggler throws balls into air. He throws one whenever the previous one is at its highest point.How high do the balls rise if he throws n balls in each second? Take acceleration due to gravity as g.

• 3)

A juggler throws balls into air. He throws one whenever the previous one is at its highest point.How high do the balls rise if he throws n balls in each second? Take acceleration due to gravity as g.

• 4)

A motor boat covers the distance between two spots on the river in t1=8 h and t2=12 h, downstream and upstream, respectively.What is the time required for the boat to cover this distance in still water?

• 5)

A train passes a station A at 40 kmh -I and maintains its speed for 7 km an? is then uniformly retarded, stopping at B which is 8.5 km from A. A second train starts from A at the instant the first train passes and being accelerated some part of the journey and uniformly retarded for the rest, stops at B at the same times as the first train. Calculate the maximum speed-of the second train, use only the graphical method.

#### 11th CBSE Physics - Units and Measurements Five Mark Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

Write down the number of significant figure in the following.
3.08 x 1011

• 2)

The refractive index of water is found to have the values 1.29,1.33,1.34,1.35,1.32,1.36,1.30 and 1.33.Calculate mean value of refractive index

• 3)

Derive the dimensions formula of physical quantities. Velocity gradient

• 4)

One mole of an ideal gas at standard temperature and pressure occupies 22.4 L(molar volume). What is the ratio of molar volume to the atomic volume of a mole of hydrogen? (Take the size of hydrogen molecule to be about 1$\mathring{A}$). Why is the ratio so large?

• 5)

Two resistors of resistance ${ R }_{ 1 }=\left( 100\pm 3 \right) \Omega$ and ${ R }_{ 2 }=\left( 200\pm 4 \right) \Omega$ are connected (i) in series, (ii) in parallel. Find the equivalent resistance of the series combination. Use for the relation R = R+ R2.

#### 11th CBSE Physics - Physical World Five Mark Question Paper - by Jemi Bhouseya - Indore - View & Read

• 1)

Tile shells of crabs found around a particular coastal location in Japan seem mostly to resemble the legendary face of a Samurai. Given below are two explanations of this observed fact. Which of these strikes you as a scientific explanation?
(a) A tragic sea accident several centuries ago drowned a young Samurai. As a tribute to his bravery, nature through its inscrutable ways immortalized his face by imprinting it on the crab shells in that area.
(b) After the sea tragedy, fishermen in that area, in a gesture of honour to their dead hero, let free any crab shell caught by them which accidentally had a shape resembling the face of a Samurai. Consequently, the particular shape of the crab shell survived longer and therefore in course of time the shape was genetically propagated. This is an example of evolution by artificial selection.
[Note: This interesting illustration taken from Carl Sagan's 'The Cosmos' highlights the fact that often strange and inexplicable facts which on the first sight appear 'supernatural' actually turn out to have simple scientific explanations. Try to think out other examples of this kind].

• 2)

Give the salient features of Einstein's theory.

• 3)

Name four fundamental forces in nature.

• 4)

Does imagination play any role in physics?

• 5)

Physics has a very limited scope and only in practice of a few blessed ones. Do you agree?

#### CBSE 11th Physics - Laws of Motion in Two Variables Three Marks Questions - by Girish - Chennai - View & Read

• 1)

A helicopter of mass 1000 kg reises with a vertical acceleration of 15m /s2. The crew and the passengers weigh 300 kg. Give the magnitude and direction of the
(iii) force on the helicopter due to the surrounding air, take g = 10 m/s2.

• 2)

A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5m with speed 40 rev/min in a horizontal plane. What is the tension in the string? what is the maximum speed with which the stone can be whirled around if the string can withstand a maximum tension of 200 N?

• 3)

An aircraft executes a horizontal loop at a speed of 720km/h with its wings banked at 15o . What is the radius of the loop?

• 4)

Ten one-rupee coins are put on top of each other on a table. Each coin has mass m.
Give the magnitude and direction of
(iii)  the reaction of the 6th coin on the 7th coin.(counted from the bottom)

• 5)

A light, inextensible string connects two blocks of mass M1, and M2. A force Facts upon MI. Find acceleration of the system and tension in siring.

#### 11th Standard CBSE Physics - Motion in a Plane Three Marks Questions - by Girish - Chennai - View & Read

• 1)

There are two displacement vectors,one of the magnitude 3m and the other of 4m.How would two vectors be added so that the magnitude of the resultant vector be
1m

• 2)

There are two displacement vectors,one of the magnitude 3m and the other of 4m.How would two vectors be added so that the magnitude of the resultant vector be
5m

• 3)

The velocity of a particle, when it is at the greatest height is $\sqrt { 2/5 }$ times its velocity when it is at half of its greatest height. Determine its angle of projection.

• 4)

Find the angle made by vector, $A=2\hat { i } +2\hat { j }$  with x-axis

• 5)

Two billiard balls are rolling on a flat table. One has the velocity components ${ v }_{ x }=1{ ms }^{ -1 },\quad { v }_{ y }=\sqrt { 3 } { ms }^{ -1 }$ and the other has components v'=2 ms-1 and v'y =2 ms-1 If both the balls start moving from the same point, what is the angle between their paths?

#### 11th Standard CBSE Physics - Motion in a Straight Line Three Marks Questions - by Girish - Chennai - View & Read

• 1)

To what height does the ball rise and after how long does the ball return to the player's hands?(Take g=9.8ms-2 and neglect air resistance)

• 2)

Read each statement below carefully and state with reasons and examples if it true or false.
A particle in 1-D motion
(i) with zero speed at an instant may have non-zero acceleration at that instant.
(ii)with zero speed may have non-zero velocity.
(iii)with constant speed must have zero acceleration
(iv)with positive value of acceleration must be speeding up.

• 3)

A particle starts moving from position of rest under a constant acceleration. It is travels a distance x in t second, what distance will it travel in next t second?

• 4)

A police van moving on a highway with a speed of 30 kmh-1 fires a bullet at a thief's car speeding away in the same direction of 192 km h-1.
If the muzle speed of the bullet is 150 ms-1 with what speed does the bullet hit the thief's car? ( Note, obtain that speed which is relevant for damaging the thief's car? )

• 5)

A person travels along a straight road for the first half with avelocity v1 and the second half with velocity v1 and the second half with velocity v2. What is the mean velocity of the person?

#### 11th Standard CBSE Physics - Units and Measurements Three Marks Questions - by Girish - Chennai - View & Read

• 1)

The sides of a rectangle are $(10.5\pm 0.2)$ cm and $(5.2\pm 0.1)$ cm. Calculate its perimeter with error limits.

• 2)

A capacitor of capacitance $C=(2.0\pm 0.1)\mu F$ is charged to a voltage $V=(20\pm 0.5)V$. Calculate the charge Q with error limits.

• 3)

Write down the number of significant figures in the following
34.000 m.

• 4)

Write down the number of significant figures in the following
0.02340 N/m.

• 5)

The length, breadth and thickness of a rectangular sheet of metal are 4.234 m, 1.005 m and 2.01 am, respectively. Give the area and volume of the sheet to correct significant figures.
Notes :
If different values of a same quantity are given different units, then first of all convert them in same units without changing the number of significant figures.

#### CBSE 11th Physics Unit 1 Physical World Three Marks Questions - by Girish - Chennai - View & Read

• 1)

It is often said that the world is witnessing now a second industrial revolution which will transform the society as radically as did the first. List some key contemporary areas of science and technology which are responsible for this revolution.

• 2)

Though the law gives women equal status in India, many people hold unscientific views on a woman's innate nature, capacity and intelligence and in practice give them a secondary status and role.
Demolish this view using scientific arguments and by quoting examples of great women in science and other spheres and persuade yourself and others that given equal opportunity, women are on par with men.

• 3)

Tile shells of crabs found around a particular coastal location in Japan seem mostly to resemble the legendary face of a Samurai. Given below are two explanations of this observed fact. Which of these strikes you as a scientific explanation?
(a) A tragic sea accident several centuries ago drowned a young Samurai. As a tribute to his bravery, nature through its inscrutable ways immortalized his face by imprinting it on the crab shells in that area.
(b) After the sea tragedy, fishermen in that area, in a gesture of honour to their dead hero, let free any crab shell caught by them which accidentally had a shape resembling the face of a Samurai. Consequently, the particular shape of the crab shell survived longer and therefore in course of time the shape was genetically propagated. This is an example of evolution by artificial selection.
[Note: This interesting illustration taken from Carl Sagan's 'The Cosmos' highlights the fact that often strange and inexplicable facts which on the first sight appear 'supernatural' actually turn out to have simple scientific explanations. Try to think out other examples of this kind].

• 4)

Textbooks on science may give you a wrong impression that studying science is dry and all too serious and that scientists are absent-minded introverts who never laugh or grin. This image of science and scientists is patently false. Scientists, like any other group of humans, have their share of humorists, and many have led their lives with a great sense of fun and adventure, even as they seriously pursued their scientific work. Two great physicists of this genre are Gamow and Feynman. You will enjoy reading their books listed in the Bibliography.

• 5)

Give the salient features of Einstein's theory.

#### CBSE 11th Physics Unit 15 Waves Two Marks Questions - by Girish - Chennai - View & Read

• 1)

What frequency of the sound you hear coming directly from the siren?

• 2)

A steel wire has a length of 12 m and a mass of 2.10 kg. What will be the speed of a transverse wave on this wire when a tension of 2.06$\times$104N is applied?

• 3)

A pipe 20 cm long is closed at one end. Which harmonic mode of the pipe is resonantly excited by a source of 1237.5 Hz? (sound velocity in air =330ms-1)

• 4)

Equation of a plane progressive wave is given by y=0.6 sin$2\pi \left( t-\frac { x }{ 2 } \right)$
On reflection from a denser medium, its amplitude becomes 2/3 of the amplitude of  incident wave. What will be equation of reflected wave?

• 5)

At what temperature (in 0C) Will be speed of sound air be 3 times its value at 00 C?

#### 11th Standard CBSE Physics - Oscillation Two Marks Questions - by Girish - Chennai - View & Read

• 1)

A body of mass 12 kg is suspended by coil spring of natural length 50 cm and force constant 2.0x103Nm-1. What is the streched length of the spring?If the bosy is pulled down further streching the spring to a length of 5.9 cm and then released,then what is the frequencyof oscillation of the suspended mass?

• 2)

A spring compressed by 0.1 m develops a restoring force 10 N. A body of mass 4 kg placed on it . Deduce
(i) the force constant of the spring
(ii) the depression of the spring under the weight of the body (take g=10 N/kg)
(iii) the period of oscillation, the body is distributed and
(iv) the frequency of oscillation

• 3)

A circular disc of mass 10 kg is suspended by a wire attached to its centre. The wire is twisted by rotating the disc and released. The period of torsional oscillation is found to be 1.5 s. The radius of the disc is 15 cm.Determine the torsional spring constant of the wire.
This is a question based on torsion pendulum for which $T=2\pi \sqrt { \frac { \quad }{ \alpha } }$
where I =moment of inertia of the disc about axis of rotation,$\alpha$ =torsion constant which is restoring couple per unit twist.

• 4)

Define the restoring force and it characterstic in case of an oscillating body.

• 5)

A particle excutes SHM of period 8 s. After what time of its passing through the mean position will be energy be half kinetic and half potential?

#### 11th Standard CBSE Physics - Kinetic Theory Two Marks Questions - by Girish - Chennai - View & Read

• 1)

The value of root mean square speed for O2 is 400 m/s. Find the temperature of the O2.

• 2)

If value of most probable speed for an ideal gas is 500 m/s. Find the value of root mean square speed for this gas.

• 3)

Find the temperature at which rms speed of a gas is half of its value of 00C, pressure remaining constant.

• 4)

We have 0.5 g of hydrogen gas in a cubic chamber of size 3 cm kept at NTP. The gas in the chamber is compressed keeping the temperature constant till a final pressure of 100 atm. Is one justified in assuming the ideal gas law, in the final state? (Hydrogen molecules can be consider as spheres of radius 1 $\overset { o }{ A }$.

• 5)

Three vessels of equal capacity have gases at the same temperature and pressure. The first vessel contains neon (monatomic), the second contains chlorine (diatomic) and the third contains uranium hexafluoride (polyatomic). Do the vessels contain equal number of respective molecules? Is the root mean square speed of molecules the same in the three cases? If not, in which case is Vrms ,the largest?

#### 11th Standard CBSE Physics - Thermodynamics Two Marks Questions - by Girish - Chennai - View & Read

• 1)

A person of mass 60 kg wants to lose 5 kg by going up and down a 10 m high stairs. Assume he burns twice as much fat while going up than coming down. If 1kg of fat is burnt on expending 7000 kcal calories, how many times must he go up and down to reduce his weight by 5 kg?

• 2)

What amount of heat must be supplied to 2.0$\times$ 10-2kg of nitrogen (at room temperature) to raise its temperature by 45°C at constant
pressure? (Molecular mass of N2 = 28, R =8.3 J mol-1 K-1)

• 3)

The efficiency of a heat engine is more in hilly area than in plain.Explain it.

• 4)

Is the coefficient of performance of a refrigerator, a constant quantity?

• 5)

Why is it theoretically not possible to have a device which create no thermal pollution?

#### 11th Standard CBSE Physics - Thermal Properties of Matter Two Marks Questions - by Girish - Chennai - View & Read

• 1)

By how much the temperature of a copper rod to be raised so as to increase its length by 1% ? Given that coefficient of linear expansion of copper = 1.7 x 10-5 K-1

• 2)

The density of mercury is $13.6\times { 10 }^{ 3 }Kg\quad { m }^{ -3 }$  at 0o C and its coefficient of volume expansion is $1.82\times { 10 }^{ -4 }{ K }^{ -1 }$  . Find the density at 50o C.

• 3)

What value of temperature in the Celsius and Fahrenheit scales give the same reading?

• 4)

There is a slight temperature different between the water fall at the top and the bottom. Why?

• 5)

Given below are observations on molar specific heats at room temperature of some common gases.

 Gas Molar specific heat  (Cv) (cal mol-1K-1) Hydrogen 4.87 Nitrogen 4.97 Oxygen 5.02 Nitric oxide 4.99 Carbon monoxide 5.01 Chlorine 6.17

The measured molar specific heats of these gases are markedly different from those for monoatomic gases.(Typically, molar specific heat of monoatomic gas is 2.92 cal/mol K). Explain this difference. What can you infer from the somewhat large (than the rest) value for chlorine?

#### 11th Standard CBSE Physics - Mechanical Properties of Fluids Two Marks Questions - by Girish - Chennai - View & Read

• 1)

Fill in the blanks using the word(s) from the list appended with each statement.
For a fluid in a steady flow, the increase in flow speed at a constriction follows from ............while the decrease of pressure there follows from (conservation of mass/Bernoulli's principle).

• 2)

Fill in the blanks using the word(s) from the list appended with each statement.
For the model of a plane in a wind tunnel, turbulence occurs at a ................. speed that the critical speed for turbulence for an actual plane (greater/smaller)

• 3)

If the required pressure in the tyre of a car is 199 kPa, then what is the absolute pressure?

• 4)

A hydraulic automobile lift is designed to lift cars with a maximum mass of 300kg. The area of cross-section of the piston carrying the load is 425 ${ cm }^{ 2 }$.What maximum pressure would the smaller piston have to bear?

• 5)

A vertical off-shore structure is built to withstand a maximum stress of ${ 10 }^{ 9 }Pa$. Is the structure suitable for putting up on top of an oil well in the ocean? Take the depth of the ocean to be roughly 3km and ignore ocean currents.

#### 11th Standard CBSE Physics - Mechanical Properties of Solids Two Marks Questions - by Girish - Chennai - View & Read

• 1)

A solid sphere of radius R made of a material of bulk modulus B is surrounded by a liqiud in a cylindrical container. A massless piston of area  A floats on the surface of the liqiud. When a mass M is placed on the piston on the piston to compress the liqiud, find fractiional change in the radius of the sphere?

• 2)

To what depth must a rubber ball be taken in deep sea so that its volume is decreased by 0.1%?

• 3)

The stress-strain graphs for materials A and B are shown in Fig. (a) and Fig. (b).

The graphs are drawn to the same scale.
(i) Which of the materials has greater Young's modulus?
(ii) Which of the two is the stronger material?

• 4)

Awire of length L and radius r is clamped rigidly at one end. When the other end of the
wire is pulled by a force j, its length increases by l. Another wire of the same material of length 2L and radius 2r, is pulled by a force 2f Find the increase in length of this wire.

• 5)

A piece of copper having a rectangular cross-section of 15.2 mm x 19.1 mm is pulled in tension with 44,500 N force, producing only elastic deformation. Calculate the resulting strain? Shear modulus of elasticity of copper is 42 x 109 N/m2.

#### CBSE 11th Physics Unit 8 Gravitation Two Marks Questions - by Girish - Chennai - View & Read

• 1)

A plant moving along an elliptical orbit is closet to the Sun at a distance r1 and farthest away at a distance of r2 . If V1 and V2 are the linear velocities at these points respectively, then find the ratio v1/v2

• 2)

If the earth be at one half of its present distance from the sun, them how many days will be there in  a year?

• 3)

Calculate the force of attraction between two bodies, each of mass 100 kg 1 m apart on the surface of the earth.

• 4)

The acceleration due to gravity on a planet is 1.96${ ms }^{ -2 }$. If it is safe to jump from a height of 2m on the earth, then what will be the corresponding safe height on the planet?

• 5)

Does the concentration of the earth's mass near its centre change the variation of g with height compared with a homogeneous sphere, how?

#### 11th Standard CBSE Physics - System of Particles and Rotational Motion Two Marks Questions - by Girish - Chennai - View & Read

• 1)

A person is standing on a rotating table with metal spheres in his hands. If he withdraw his hands to his chest, what will be the effect on his angular velocity?

• 2)

Two boys of the same weight it at the opposite ends of a diameter of a rotating circular table. What happens to the speed of rotation if they move nearer to the axis of rotation?

• 3)

If ice on poles melts, then what is the change in duration of day?

• 4)

A solid cylinder of mass 20 kg rotates about its axis with angular speed of 100 rad/s. The radius of cylinder is 0.25m. What is KE of rotation of cylinder?

• 5)

If earth contract to half its radius. What would be the length of the day?

#### 11th Standard CBSE Physics - Work, Energy and Power Two Marks Questions - by Girish - Chennai - View & Read

• 1)

Calculate the velocity of the bob of a simple pendulum at its mean position if it is able to rise to a vertical height of 10 cm. [g=9.8 m/s2]

• 2)

Can a body have without momentum? If yes, then explain how they are related with each other?

• 3)

A spring balance reads forces in Newtons. The scale is 20 cm long and read from 0 to 60 N. Find potential energy of spring when the scale reads 20 N.

• 4)

A steel spring of spring constant 150 N/m is compressed from its natural position through a mud wall 1m thick, the speed of bullet drops to 100m/s. Calculate the average resistance of the wall. Neglect friction of air.

• 5)

A trolley of mass 300 kg carrying a sand bag of 25 Kg is moving uniformly with a speed of 27km/h on a frictionless track. After a while , sand starts leaking out of a whole on the floor of the trolley at the rate of 0.052 kg-1.What is the speed of the trolley after the entire sand bag is empty?

#### 11th CBSE Physics - Laws of Motion Book Back Questions - by Girish - Chennai - View & Read

• 1)

Why are porcelain objects wrapped in paper or straw before packing for transportation ?

• 2)

A passenger of mass 72.2 kg is riding in an elevator while standing on a platform scale. What does the scale read when the elevator cab is
(i) descending with constant velocity
(ii) ascending with constant acceleration, 3.5 m/s2?

• 3)

A force of 128 If acts on a mass of 490 g for 10 s. What velocity will it give to the mass ?

• 4)

A body of mass 2 kg is being dragged with a uniform velocity of 2 ms -1 on a rough horizontal plane. The coefficient of friction between the body and the surface is 0.2. Calculate the amount of heat generated per second. Take  g =9.8 ms-2 and J = 1.2Jcal-1

• 5)

Explain why passengers are thrown forward from their seats when a speeding bus stops suddenly,

#### 11th Physics - Motion in a Plane Two Marks Questions - by Girish - Chennai - View & Read

• 1)

We can order events in time and there is no sense of time, distinguishing past, present and future. Is time a vector?

• 2)

The angle between vector A and B is 600  .What is the ratio of A.B and $\left| A\times B \right|$ ?

• 3)

A person sitting in a running train throws a ball vertically upwards. What is the nature of the path described by the ball to a person?
Sitting inside the train

• 4)

A railway carriage moves over a straight track with acceleration a. A passenger in the carriage drops a stone. What is the acceleration of the stone w.r.t. the carriage and the earth?

• 5)

When a large star becomes a supernova, its core may be compressed so tightly that it becomes a neutron star, with a radius of about 20km. If a neutron star rotates once every second, What is the magnitude of the particle's centripetal acceleratiom?

#### CBSE 11th Physics - Motion in a Straight Line Book Back Questions - by Girish - Chennai - View & Read

• 1)

For what condiion, an object could be considered as a point object? Describe in brief

• 2)

The displacement o a particle is given by at2. What is the dependency of accleration on time?

• 3)

Thye position x of a body is given by x = A sin(wt). Find the time at which the displacements is maximum.

• 4)

What are uses of a velocity  - time graph ?

• 5)

The position of an object is given by x  = 2t2+st. Find out that its motion is uniform and nonuniform.

#### CBSE 11th Physics Unit 2 - Units and Measurements Two Marks Questions - by Girish - Chennai - View & Read

• 1)

A new unit of length is chosen such that the speed of light in vacuum is unity. What is the distance between the sun and the earth in terms of the new unit, if light takes 8min and 20 s to cover this distance?

• 2)

Express an acceleration of 10 m/s2 in km/h2.

• 3)

Which of the following length measurement is most accurate and why? 40.00 cm

• 4)

What is common between bar and torr?

• 5)

Calculate the surface area of a solid cylinder of diameter 4 cm and height 20 cm in mm2

#### CBSE 11th Physics - Physical World Two Marks Questions - by Girish - Chennai - View & Read

• 1)

Some of the most profound statements on the nature of science have come from Albert Einstein, one of the greatest scientists of all time. What do you think did Einstein mean when he said, "The most incomprehensible thing about the world is that it is comprehensible"?

• 2)

Politics is the art of possible. Similarly, Science is the art of the soluble. Explain this beautiful aphorism on the nature and practice of science.

• 3)

Though India now has a large base in science and technology which is fast expanding, it is still a long way for realizing its potential for becoming a world leader in Science. Name some important factors, which in your view have hindered the advancement of science in India.

• 4)

The industrial revolution in England and Western Europe more than two centuries ago was triggered by some key scientific and technological advances. What were these advances?

• 5)

Name the two most important contributions of Albert Einstein.

#### CBSE 11th Physics - Waves Book Back Questions - by Girish - Chennai - View & Read

• 1)

What are echo and acoustics?

• 2)

What is the nature of water waves produced by a motorboat sailing in water ?

• 3)

In a hot summer day, pitch of an organ pipe will be higher or lower?

• 4)

Show that when a string fixed at its two ends vibrates in 1 loop, 2 loops, 3loops and 4loops, the frequencies are in the ratio 1:2:3:4.

• 5)

When two waves of almost equal frequencies n1 and n2 reach at a point, simultaneously. What is the time interval between successive maxima?

#### CBSE 11th Physics - Oscillation Book Back Questions - by Girish - Chennai - View & Read

• 1)

Two simple pendulums of equal length cross each other at mean position. What is their phase difference?

• 2)

A body executes SHM with aperiod of 11/7 s and an amplitude of 0.025 m. What is the maximum value of acceleration?

• 3)

What is the force equation of a SHM?

• 4)

Under what condition is the motion of a simple pendulum be simple harmonic?

• 5)

What is the ratio between the distance travelled by the oscillator iin one time period and amplitude?

#### CBSE 11th Physics Unit 13 Kinetic Theory Book Back Questions - by Girish - Chennai - View & Read

• 1)

If a gas is heated, its temperature increases. On the basis of kinetic theory of gases, explain.

• 2)

Hoe degree of freedom of a gas molecule is related with the temperature?

• 3)

Is molar specific heat of a solid, a constant quantity?

• 4)

If a molecule having N atoms has k number of constraints, how many degree of freedom does the gas possess?

• 5)

If there are f degrees of freedom with n moles of a gas, then find the internal energy possessed at a temperature T.

#### CBSE 11th Physics Unit 11 Thermal Properties of Matter Book Back Questions - by Girish - Chennai - View & Read

• 1)

Why birds are often seen to swell their features in winter?

• 2)

Two bodies at different temperatures T1 and T2, if brought in thermal contact do not necessarily settle at the mean temperature $\frac { ({ T }_{ 1 }+{ T }_{ 2 }) }{ 2 }$ . Why?

• 3)

Usually a good conductor of heat is a good conductor of electricity also. Give reason.

• 4)

Why the temperature above 12000C cannot be measured accurately by a platinum resistance thermometer?

• 5)

A tightened glass stopper can be taken out easily by pouring hot water around the neck of the bottle. Why?

#### CBSE 11th Physics Unit 12 Thermodynamics Book Back Questions - by Girish - Chennai - View & Read

• 1)

Two isothermal curves do not intersect each other, why?

• 2)

Why air quickly leaking out of a balloon becomes cooler?

• 3)

A room can be cooled by opening the door of a refrigerator.Is it true or false?

• 4)

Is reversible process possible in nature?

• 5)

On what factors, the efficiency of a Carnot engine depends?

#### CBSE 11th Physics - Mechanical Properties of Fluids Book Back Questions - by Girish - Chennai - View & Read

• 1)

How a raincoat become rainproof?

• 2)

Can Bernoulli's equation be used to describe the flow of water through a rapid in a river? Explain.

• 3)

Three vessels have same base area and different neck area. Equal volume of liquid is poured into them, which will possess more pressure at the base?

• 4)

What us the use of open tube manometer?

• 5)

A mercury barometer is placed in the mercury through in a way that angle mad with the vertical is ${ 60 }^{ \circ }$.Find the height of mercury column.

#### CBSE 11th Physics - Mechanical Properties of Solids Book Back Questions - by Girish - Chennai - View & Read

• 1)

Stress and pressure are both forces per unit area. Then, in what respect does stress differ from pressure ?

• 2)

Which type of strain is there, when a spiral spring is stretched by a force ?

• 3)

What does the slope of stress versus strain graph indicate ?

• 4)

What is Bulk modulud for a perfectly rigid body?

• 5)

A wire 50cm long and 1 sq mm is cross-section has the Young's modulus, Y=2x1010Nm-2 . How much work is done in stretching the wire through 1 mm?

#### 11th Standard CBSE Physics - Gravitation Book Back Questions - by Girish - Chennai - View & Read

• 1)

From Kepler's second law and observations of the sun's motion as seen from the earth, we can conclude that the earth is closer to the sun during winter in the Northern hemisphere than during sumer. Explain

• 2)

Are the Kepler's laws applicable only to the solar system?

• 3)

Can we determine the mass of a satellite by measuring its time period?

• 4)

What is a parking orbit?

• 5)

If the earth is regarded as a hollow sphere, then what is the weight of an object below surface of the earth?

#### 11th Standard CBSE Physics - System of Particles and Rotational Motion Book Back Questions - by Girish - Chennai - View & Read

• 1)

Can the mass of body be taken to be concentrated at its centre of mass for the purpose of calculating its rotational inertia?

• 2)

A cricket bat is cut through its centre of mass into two parts as shown. Then, state whether both parts are of same mass or not. Also, give a reason.

• 3)

Why in hand driven grinding machine, a handle is put near the circumference of the stone or wheel?

• 4)

The bottom of a ship is made heavy. Why?

• 5)

The moment of inertia of a disc about its diameter is $\frac { { MR }^{ 2 } }{ 4 }$ , what will be its moment of inertia, an axis tangential to it and parallel to one of its diameter? [where M is mass of the disc and R is its radius.]

#### 11th Standard CBSE Physics - Work, Energy and Power Book Back Questions - by Girish - Chennai - View & Read

• 1)

A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

• 2)

A body is moving unidirectionally under the influence of a source of constant power. Its displacement in time t is proportional to

• 3)

How much work is done by mass M moving once around a horizontal circle of radius r?

• 4)

What is the coefficient of restitution?

• 5)

Is the total linear momentum conserved during the short time of an elastic of two balls?

#### 11th Standard CBSE Physics Unit 5 Laws of Motion Book Back Questions - by Girish - Chennai - View & Read

• 1)

If force is acting on a moving body perpendicular to the direction of motion, then what will be its effect on the speed and direction of the body ?

• 2)

Calculate them impulse necessary to step 1500 kg car  travelling at 90 km/h.

• 3)

Why is static friction called a self-adjusting force?

• 4)

A body is moving in a circular path such that its speed always remains constant. Should there be a force action on the body?

• 5)

The mountain road is generally made winding upwards rather than going straight up. Why?

#### 11th Standard CBSE Physics Unit 4 Motion in a Plane Book Back Questions - by Girish - Chennai - View & Read

• 1)

If $|A\times B|=A.B$, What is the angle between A and B?

• 2)

What is the angle between A and B, if A and B denote the adjacent sides of a parallelogram drawn from a point and the area of the parallelogram is 1/2 AB?

• 3)

When the sum of the two vectors maximum and minimum?

• 4)

If,$|A+B|=|A-B|$ What is the angle between  A and B?

• 5)

If A.B = $|A\times B|$, Find the value of angle between A and B.

#### 11th Standard CBSE Physics Unit 3 Motion in a Straight Line Book Back Questions - by Girish - Chennai - View & Read

• 1)

The displacement-time graph of a particle is parallel to time-axis, what is the velocity of the particle?

• 2)

Is it possible that x-t graph could have negative slope?

• 3)

With zero speed a particle may have non-zero velocity. Is the statement true or false, explain?

• 4)

Is itpossible that a body could have constant speed but varying velocity?

• 5)

Is it possible that a body have a constant velocity but varying speed?

#### 11th Standard CBSE Physics Unit 2 - Units and Measurements Book Back Questions - by Girish - Chennai - View & Read

• 1)

The SI units of magnetic field is

• 2)

A physical quantity is represented by X = Ma Lb T-c . If percentage error in the measurement of M, Land Tare $\alpha$%, $\beta$% and $\gamma$% respectively, then total percentage error is

• 3)

The velocity of a body moving in viscous medium is given by v =$\frac { A }{ B } \left[ 1-{ e }^{ \frac { -t }{ b } } \right]$where t is time, A and B are constants
Then the dimensions ot A are

• 4)

Is it possible to have length and velocity both as fundamental quantities?Why?

• 5)

What is the difference between nm, mN and Nm?

#### 11th Standard CBSE Physics Unit 1 Physical World Book Back Questions - by Girish - Chennai - View & Read

• 1)

Who gave theory of relativity?

• 2)

Who proposed the wave theory of light?

• 3)

The name of the particle 'Boson' is associated with the name of :

• 4)

Who did not discover radioactivity?

• 5)

Arrange four types of basic forces in the order of increasing strength in code using a, b, c and d.

#### 11th Standard CBSE Physics Unit 9 Mechanical Properties of Solids One Mark Question and Answer - by Girish - Chennai - View & Read

• 1)

Dimensional formula of stress is same as that of

• 2)

Young's modulus of a material has the same unit as

• 3)

Elastic limit is equal to

• 4)

Which of the following is not a unit of Young's modulus?

• 5)

A wire suspended vertically from one end, is stretched by attaching a weight 200 N to the lower end. The weight stretches the wire by 1 mm. The energy gained by the wire is

#### 11th Standard CBSE Physics Unit 8 Gravitation One Mark Question with Answer Key - by Girish - Chennai - View & Read

• 1)

A satellite is orbiting the earth. If its distance from the earth is increased, its

• 2)

If g is the acceleration due to gravity on the earth's surface, the gain in the potential energy of an object of mass m raised from the earth's surface to a height equal to the radius R of the earth,is

• 3)

If three uniform spheres, each having mass M and radius r, are kept in such a way that each touches the other two, the magnitude of the gravitational force on any sphere due to the other two is

• 4)

A satellite of mass m revolves around the earth of radius R at a height x from its surface. If g is the acceleration due to gravity on the surface of the earth, the orbital speed of the satellite is

• 5)

Mars has about 1/10th as much mass as the earth and half as great a diameter. TI1e acceleration of a falling body on Mars is about

#### 11th Standard CBSE Physics Unit 7 System of Particles and Rotational Motion One Mark Question and Answer - by Girish - Chennai - View & Read

• 1)

A ball is moving with a velocity of 10m/s. Suddenly, it breaks into two equal parts. What will be the speed of centre of mass of the system after explosion?

• 2)

A particle is moving on the x-axis with a linear velocity of 2 m/s. What will be its angular momentum about the origin?

• 3)

Why is moment of inertia also called rotational inertia?

• 4)

Does the moment of inertia of a rigid body change with the speed of rotation?

• 5)

Two solid spheres of the same mass are made of metals of different densities. Which of them has a larger moment of inertia about the diameter?

#### 11th Standard CBSE Physics Unit 6 Work, Energy and Power One Mark Question and Answer - by Girish - Chennai - View & Read

• 1)

A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

• 2)

A body is moving unidirectionally under the influence of a source of constant power. Its displacement in time t is proportional to

• 3)

The work done by all the forces (external and internal) on a system equals the change in

• 4)

A heavy stone is thrown from a cliff of height h with a speed v. The stone will hit the ground with maximum speed if it is thrown

• 5)

Two bodies of masses m and 4 m are moving with equal kinetic energy. The ratio of their linear momenta is

#### 11th Standard CBSE Physics Unit 4 Laws of Motion One Mark Question with Answer Key - by Girish - Chennai - View & Read

• 1)

If the tension in the cable supporting an elevator is equal to the weight of the elevator, the elevator may

• 2)

The dimension of Impulse is

• 3)

A block of mass M is pulled along a horizontal frictionless surface by a rope of mass m.
Force P is applied at one end of the rope. The force which the rope exerts on the block is:

• 4)

Action and reaction

• 5)

A force of 200 N is required to push a car of mass 500 kg slowly at constant speed on a level road. If a force of 500 N is applied, the acceleration of the car (in m S-2) will be

#### 11th Standard CBSE Physics Unit 4 Motion in a Plane One Mark Question and Answer - by Girish - Chennai - View & Read

• 1)

If $\overrightarrow { { a }_{ 1 } }$ and $\overrightarrow { { a }_{ 2 } }$ are two non collinear unit vectors and if $\left| \overrightarrow { { a }_{ 1 } } +\overrightarrow { { a }_{ 2 } } \right|$ =$\sqrt{3}$, then the value of $\left( \overrightarrow { { a }_{ 1 } } -\overrightarrow { { a }_{ 2 } } \right) .\left( 2\overrightarrow { { a }_{ 1 } } +\overrightarrow { { a }_{ 2 } } \right)$ is

• 2)

If the resultant of three forces $\overrightarrow { F } _{ 1 }=p\hat { i } +3\hat { j } -\hat { k } ,\overrightarrow { F } _{ 2 }$and $\overrightarrow { F } _{ 3 }=6\hat { i } -\hat { k }$ acting on a particle has a magnitude equal to 5 units, then the value of p is

• 3)

A boy aims a gun at a target from a point, at a horizontal distance of 100 m. if the gun can impart a horizontal velocity of 500 ms-1 to the bullet, the height above the target where he must aim his gun, in order to hit it is (Take g = 10 ms=-2)

• 4)

At the top of the trajectory of a projectile, the directions of its velocity and accelerations are

• 5)

A plane is indined at an angle of 30° with horizontal. The magnitude of component of a vector $\overset\rightarrow{A}$=-10$\hat{k}$ perpendicular to this plane is (here z-direction is vertically upwards

#### 11th CBSE Physics Unit 3 Motion in a Straight Line One Mark Question Paper and Answer - by Girish - Chennai - View & Read

• 1)

The displacement x of a particle varies with time according to the relation x=$\frac { a }{ b }$(1-e-bt). Then

• 2)

Which of the following is not a vector quantity?

• 3)

When the distance travelled by a body is directly proportional to the time, the body is said to have a

• 4)

In case of a moving body

• 5)

Identify one dimensional motion out of the following:

#### 11th CBSE Physics Unit 2 Units and Measurements One Mark Question Paper - by Girish - Chennai - View & Read

• 1)

The dimensions of energy per unit volume are the same as those of

• 2)

The SI units of the universal gravitational constant G are

• 3)

The density of a cube is measured by measuring its mass and the length of its sides. If the maximum errors in the measurement of mass and length are 3% and 2% respectively, then the maximum error in the measurement of density is

• 4)

The velocity of a body moving in viscous medium is given by v =$\frac { A }{ B } \left[ 1-{ e }^{ \frac { -t }{ b } } \right]$where t is time, A and B are constants
Then the dimensions ot A are

• 5)

The dimensions of entropy are

#### Physical World One Mark Questions - by Girish - Chennai - View & Read

• 1)

Who discovered cosmic radiations?

• 2)

Who gave Universal Law of Gravitation?

• 3)

Which scientific principle is steam engine based on:

• 4)

Who proposed the wave theory of light?

• 5)

The name of the particle 'Boson' is associated with the name of :

#### 11th CBSE Thermal Properties of Matter Model Question Paper - by Girish - Chennai - View & Read

• 1)

At about 4°C, a certain amount of water has maximum

• 2)

Dimensional formula of specific heat capacity is

• 3)

The top of a lake gets frozen at a place where the surrounding air is at a temperature of - 20°C. Then

• 4)

The scale on a steel meter rod is calibrated at 20°C. What will be the error in the reading of 50 ern at 27°C? Take, a = 1.2 x 10.5 °C-1

• 5)

The rates of cooling of two different liquids put in exactly similar calorimeters and kept in identical surroundings are the same if

#### 11th CBSE Physics Mechanical Properties of Fluids Model Question Paper - by Girish - Chennai - View & Read

• 1)

The Bernauli's Theorem is based on the conservation of:

• 2)

Two small drops of mercury, each of radius R, coalesce to form a single large drop. The ratio of the total surface energies before and after the change is:

• 3)

For a ball falling in a liquid with constant velocity, ratio of resistance force due to the liquid to that due to gravity is

• 4)

Application of Bernaull's Theorem can be seen in

• 5)

At which of the following temperature, the value of surface tension of water is minimum?

#### 11th Standard CBSE Physics Mechanical Properties of Solids Model Question Paper - by Girish - Chennai - View & Read

• 1)

Dimensional formula of stress is same as that of

• 2)

Young's modulus of a material has the same unit as

• 3)

Which of the following is not a unit of Young's modulus?

• 4)

A spring of force constant k is cut into two equal parts. The force constant of each part is

• 5)

Young's modulus of a wire depends on

#### 11th Standard CBSE Physics Gravitation Model Question Paper - by Girish - Chennai - View & Read

• 1)

A satellite is orbiting the earth. If its distance from the earth is increased, its

• 2)

A satellite of mass m revolves around the earth of radius R at a height x from its surface. If g is the acceleration due to gravity on the surface of the earth, the orbital speed of the satellite is

• 3)

If a particle is fired vertically upwards from the surface of earth and reaches a height of 6400 km, the initial velocity of the particle is (assume R = 6400 km and g = 10 ms-2)

• 4)

If M is the mass of the earth and R its radius, the ratio of the gravitational acceleration and the gravitational constant is

• 5)

A satellite is launched into a circular orbit of radius R around the earth. A second satellite launched into an orbit of radius 1.01 R. The time period of the second satellite is larger than that of the first one by approximately

#### 11th Standard CBSE Unit 7 System of Particles and Rotational Motion Model Questions Paper - by Girish - Chennai - View & Read

• 1)

A couple produces a:

• 2)

A cylindrical solid of mass M has raidus R and length L. Its moment of inertia about a generator is:

• 3)

A man of mass M is standing at the centre of a rotating turn table rotating with an angular velocity w. The man holds two 'dumb bells' of mass M/4 each in each of his two hands. If he stretches his arms to a horizontal position, the turn table acquires a new angular velocity w' where

• 4)

A particle performing uniform circular motion has angular momentum L. If its angular frequency is doubled and its kinetic energy halved, then the new angular momentum is

• 5)

A loaded spring gun of mass M fires a 'shot' of mass m with a velocity $\vartheta$ at an angle of elevation $\theta$. The gun is initially at rest on a horizontal frictionless surface. After firing, the centre of mass of the gun-shot system

#### 11th CBSE Physics Unit 6 Work,Energy and Power Model Question Paper - by Girish - Chennai - View & Read

• 1)

A body is initially at rest. It undergoes one-dimensional motion with constant acceleration. The power delivered to it at time t is proportional to

• 2)

A body is moving unidirectionally under the influence of a source of constant power. Its displacement in time t is proportional to

• 3)

Equal masses (m each) are attached at the two ends of a string passing over two pulleys. Another mass is attached at the centre of the string. In order that there is no sag in the string, this mass should be

• 4)

A heavy stone is thrown from a cliff of height h with a speed v. The stone will hit the ground with maximum speed if it is thrown

• 5)

The work done by the external forces on a system equals the change in

#### 11th CBSE Physics Unit 5 Laws of Motion Important Question Paper - by Girish - Chennai - View & Read

• 1)

If the tension in the cable supporting an elevator is equal to the weight of the elevator, the elevator may

• 2)

A block of mass M is pulled along a horizontal frictionless surface by a rope of mass m.
Force P is applied at one end of the rope. The force which the rope exerts on the block is:

• 3)

A force of 200 N is required to push a car of mass 500 kg slowly at constant speed on a level road. If a force of 500 N is applied, the acceleration of the car (in m S-2) will be

• 4)

Water is poured from a height of 10m into an empty barrel at the rate of 1 litre per second. If the weight of the barrel is 10 kg, the weight indicated at time t = 60 s will be

• 5)

The physical quantity which is equal to the change in momentum of a body is known as

#### 11th Standard CBSE Physics Unit 4 Motion in a Plane Important Question Paper - by Girish - Chennai - View & Read

• 1)

If $\overrightarrow { { a }_{ 1 } }$ and $\overrightarrow { { a }_{ 2 } }$ are two non collinear unit vectors and if $\left| \overrightarrow { { a }_{ 1 } } +\overrightarrow { { a }_{ 2 } } \right|$ =$\sqrt{3}$, then the value of $\left( \overrightarrow { { a }_{ 1 } } -\overrightarrow { { a }_{ 2 } } \right) .\left( 2\overrightarrow { { a }_{ 1 } } +\overrightarrow { { a }_{ 2 } } \right)$ is

• 2)

The sum of magnitudes of two forces acting at a point is 18 units and the magnitude of their resultant is 12 units. The resultant is at 90° with the force of the smaller magnitude. The magnitude of the individual forces is

• 3)

From the top of a tower of height 40 m, a ball is projected upwards with a speed of 20 m/ s at an angle of elevation of 30°. The ratio of the total time taken by the ball to hit the ground to its time of flight (time taken to come back to the same elevation) is (Take g = 10 m/s2)

• 4)

A boy aims a gun at a target from a point, at a horizontal distance of 100 m. if the gun can impart a horizontal velocity of 500 ms-1 to the bullet, the height above the target where he must aim his gun, in order to hit it is (Take g = 10 ms=-2)

• 5)

At the top of the trajectory of a projectile, the directions of its velocity and accelerations are

#### 11th Standard CBSE Physics Unit 3 Motion in a Straight Line Important Question Paper - by Girish - Chennai - View & Read

• 1)

The displacement x of a particle varies with time according to the relation x=$\frac { a }{ b }$(1-e-bt). Then

• 2)

The displacement of an object at any instant is given by x = 30 + 20 t2, where x is in metres and t in seconds.
The acceleration of the object will be

• 3)

Which of the following is not a vector quantity?

• 4)

When the distance travelled by a body is directly proportional to the time, the body is said to have a

• 5)

In case of a moving body

#### 11th CBSE Physics Unit 2 Units and Measurements Important Question Paper - by Girish - Chennai - View & Read

• 1)

The SI units of magnetic field is

• 2)

The dimensions of energy per unit volume are the same as those of

• 3)

The SI units of the universal gravitational constant G are

• 4)

'Parsec' is the unit of:

• 5)

The density of a cube is measured by measuring its mass and the length of its sides. If the maximum errors in the measurement of mass and length are 3% and 2% respectively, then the maximum error in the measurement of density is

#### 11th CBSE Physics Unit 1 Physical World Important Question Paper - by Girish - Chennai - View & Read

• 1)

Who discovered cosmic radiations?

• 2)

Who gave Universal Law of Gravitation?

• 3)

What is the relative magnitude of electromagnetic force with respect to strong nuclear forces?

• 4)

Who discovered scattering of light?

• 5)

Which scientific principle is steam engine based on:

#### CBSE 11th Physics HOTs Model Exam Questions and Answers - by Bala - View & Read

• 1)

Name the two domains of Physics.

• 2)

Write the dimensional formula of wavelength and frequency of a wave.

• 3)

Can a body have zero velocity and finite acceleration?

• 4)

A body is projected with speed u at an angle $\theta$ to the horizontal to have maximum range. What is the velocity at the highest point?

• 5)

What is the coordinates for precession?

#### CBSE 11th Physics Class NCERT Questions and Answers Download - by Bala - View & Read

• 1)

Name two major groups of Physics.

• 2)

How do we make the choice of a standard / unit of measurement?

• 3)

Draw x-t graph for positive acceleration.

• 4)

Galileo, in his book 'Two new sciences', stated that for elevations which exceed or fall short of ${ 45 }^{ \circ }$by equal amounts, the ranges are equal, Prove this statement.

• 5)

What is couple?

#### Class 11 CBSE Physics Model Question and answers NCERT - by Bala - View & Read

• 1)

How much stronger nuclear force is compared to electromagnetic force?

• 2)

Name some physical quantities which are dimensionless.

• 3)

Draw v-t graph for non-uniform accelerated motion.

• 4)

Can there be two vectors where the resultant is equal to either of them?

• 5)

A wheel of moment of inertia 50 kg-m2 about its own axis is revolving at a rate of 5 revolutions per second. What is its angular momentum?

#### Oscillation Important Questions from CBSE 11th Physics - by Bala - View & Read

• 1)

What is the period of each of the function, sec$\omega$ and cosec $\omega$ t?

• 2)

What would be the effect on the time period if the amplitude of a simple pendulum increases?

• 3)

What is the force equation of a SHM?

• 4)

A simple pendulum is transferred from earth to the surface of moon. How will its time period be affected?

• 5)

The piston in the cylinder head of a locomotive has a stroke (twice the amplitude) of 1.0 m. If the piston executes simple harmonic motion with an angular frequency of 200 rad/min, then what is its maximum speed?

#### 11th CBSE Physics Kinetic Theory Important Question Paper - by Bala - View & Read

• 1)

What is the value of $\gamma$ to monoatomic gas ?

• 2)

When air is pumped into a cycle tyre the volume and pressure of the air in the tyre both are increased." What about Boyle's law in this case?

• 3)

If a gas is heated, its temperature increases. On the basis of kinetic theory of gases, explain.

• 4)

If a molecule having N atoms has k number of constraints, how many degree of freedom does the gas possess?

• 5)

If there are f degrees of freedom with n moles of a gas, then find the internal energy possessed at a temperature T.

#### 11th Physics Oscillation Important Question Paper - by Bala - View & Read

• 1)

What is the period of each of the function, sec$\omega$ and cosec $\omega$ t?

• 2)

A body executes SHM with aperiod of 11/7 s and an amplitude of 0.025 m. What is the maximum value of acceleration?

• 3)

What is the force equation of a SHM?

• 4)

If the length of a simple pendulum is increased by 25% then what is the change in its time period?

• 5)

State the condition when motion of a particle can be an SHM.

### CBSE Education Study Materials

#### 11th CBSE Physics 2019 - 2020 Academic Syllabus - by Girish - Chennai Aug 21, 2019 Aug 21, 2019

Physics 2019 - 2020 Academic Syllabus

#### Tips to score good marks in CBSE Class 11 Physics - by ADMIN-ENGLISH Jan 23, 2019 Jan 23, 2019

• Practice the important questions from these chapters. Below is the sample question paper f...

#### Tips and Tricks to score good marks in CBSE Class 11 Physics - by ADMIN-ENGLISH Jan 23, 2019 Jan 23, 2019

Scoring good marks in physics is easy if you work on derivations ( important) and numerical. Phys...

#### Tips and Tricks to score good marks in CBSE Class 11 Physics - by Bala Jan 12, 2019 Jan 12, 2019

Scoring good marks in physics is easy if you work on derivations ( important) and numerical. Phys...

#### CBSEStudy Material - Sample Question Papers with Solutions for Class 11 Session 2019 - 2020

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