### 12th Standard Physics Study material & Free Online Practice Tests - View Model Question Papers with Solutions for Class 12 Session 2020 - 2021 TN Stateboard [ Chapter , Marks , Book Back, Creative & Term Based Questions Papers - Syllabus, Study Materials, MCQ's Practice Tests etc..]

#### 12th Standard English Medium Physics Reduced syllabus Annual Exam Model Question Paper with Answer key - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Two identical point charges of magnitude –q are fi xed as shown in the fi gure below. A third charge +q is placed midway between the two charges at the point P. Suppose this charge +q is displaced a small distance from the point P in the directions indicated by the arrows, in which direction(s) will +q be stable with respect to the displacement

• 2)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 3)

The relative permittivity of water is _______.

• 4)

A toaster operating at 240 V has a resistance of 120 Ω. Th e power is

• 5)

In a large building, there are 15 bulbs of 40W, 5 bulbs of 100W, 5 fans of 80W and 1 heater of 1kW are connected. The voltage of electric mains is 220V. The minimum capacity of the main fuse of the building will be

#### 12th Standard English Medium Physics Reduced syllabus Annual Exam Model Question Paper - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Two identical point charges of magnitude –q are fi xed as shown in the fi gure below. A third charge +q is placed midway between the two charges at the point P. Suppose this charge +q is displaced a small distance from the point P in the directions indicated by the arrows, in which direction(s) will +q be stable with respect to the displacement

• 2)

Rank the electrostatic potential energies for the given system of charges in increasing order.

• 3)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 4)

Th e following graph shows current versus voltage values of some unknown conductor. What is the resistance of this conductor?

• 5)

A carbon resistor of (47 ± 4.7 ) k Ω to be marked with rings of diff erent colours for its identifi cation. Th e colour code sequence will be

#### 12th Standard English Medium Physics Reduced syllabus Public Exam Model Question Paper with Answer key - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Two identical conducting balls having positive charges q1 and q2 are separated by a center to center distance r. If they are made to touch each other and then separated to the same distance, the force between them will be

• 2)

Rank the electrostatic potential energies for the given system of charges in increasing order.

• 3)

Two metallic spheres of radii 1 cm and 3 cm are given charges of -1 x 10-2 C and 5 x 10-2 C respectively. If these are connected by a conducting wire, the final charge on the bigger sphere is

• 4)

There is a current of 1.0 A in the circuit shown below. What is the resistance of P ?

• 5)

A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of

#### 12th Standard English Medium Physics Reduced syllabus Public Exam Model Question Paper - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

An electric dipole is placed at an alignment angle of 300 with an electric fi eld of 2 × 105 NC-1. It experiences a torque equal to 8 N m. Th e charge on the dipole if the dipole length is 1 cm is

• 2)

Two metallic spheres of radii 1 cm and 3 cm are given charges of -1 x 10-2 C and 5 x 10-2 C respectively. If these are connected by a conducting wire, the final charge on the bigger sphere is

• 3)

_______ and Coulomb's law form fundamental principles of electrostatics

• 4)

The electric potential V as a function of distance x (metres) is given by V = ( 5x2 + 10x -9) volt. The value of electric field at a point x = 1m is

• 5)

At Infinity (i.e r = ∞), the electrostatic potential (V) is

#### 12th Standard English Medium Physics Reduced syllabus Creative Five mark Question with Answerkey - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 2)

A wire of resistance 2 ohms per meter is bent to form a circle of radius 1m. Th e equivalent resistance between its two diametrically opposite points, A and B as shown in the fi gure is

• 3)

A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of

• 4)

Th e force experienced by a particle having mass m and charge q accelerated through a potential diff erence V when it is kept under perpendicular magnetic field $\vec { B }$ is

• 5)

The BH curve for a ferromagnetic material is shown in the figure. The material is placed inside a long solenoid which contains 1000 turns/cm. The current that should be passed in the solenonid to demagnetize the ferromagnet completely is

#### 12th Standard English Medium Physics Reduced syllabus Creative Three mark Question with Answerkey - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

Define potential difference and derive.

• 2)

Derive an expression for electric flus in a non uniform electric field and an arbitrarily shaped area.

• 3)

What is dielectrics or insulators.

• 4)

(a) Distinguish between electric cells and batteries.
(b) Explain its function

• 5)

Find the expression for the equivalent emf & internal resistance of the series combination of cells

#### 12th Standard English Medium Physics Reduced syllabus Creative two mark Question with Answerkey - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

When does a dielectric said to be polarized?

• 2)

What is the electric flux through a cube of side 1cm which encloses on electric dipole?

• 3)

What orientation of an electric dipole in a uniform electric field corresponds to its
(i) stable and
(ii) unstable equilibrium? Depict the orientations.

• 4)

Two isolated metal spheres A &B have radii R & 2R respectively and same charge q. Find which of the two spheres have greater energy density just outside the surface of the sphere.

• 5)

The electric field due to a point charge depends on the distance r as parallely indicate how each of the following quantities depends on r?
a. Intensity of light from a point source.
b. Electrical potential due to a point charge.
c. Electrical potential at a distance r from to centre of a charged metallic sphere Given r < radius of the sphere.

#### 12th Standard English Medium Physics Reduced syllabus Creative one mark Question with Answerkey - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

The torque experienced by a rectangular current loop placed perpendicular to a uniform magnetic field is

• 2)

Lenz's law is in accordance with the law of

• 3)

The efficiency of an ideal transformer is

• 4)

The average power consumed per cycle is:

• 5)

An object is placed at 20 cm from a convex mirror of focal length 10 cm. The image formed by the mirror is

#### 12th Standard English Medium Physics Reduced syllabus Five mark important Questions with Answer key - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

A parallel plate capacitor has square plates of side 5 cm and separated by a distance of 1 mm.
(a) Calculate the capacitance of this capacitor.
(b) If a 10 V battery is connected to the capacitor, what is the charge stored in any one of the plates? (The value of εo = 8.85 x 10-12 Nm2 C-2)

• 2)

Dielectric strength of air is 3 × 106 V m-1. Suppose the radius of a hollow sphere in the Van de Graff generator is R = 0.5 m, calculate the maximum potential difference created by this Van de Graaff generator.

• 3)

Five identical charges Q are placed equidistant on a semicircle as shown in the figure. Another point charge q is kept at the center of the circle of radius R. Calculate the electrostatic force experienced by the charge q.

• 4)

The electrostatic potential is given as a function of x in figure (a) and (b). Calculate the corresponding electric fields in regions A, B, C and D. Plot the electric field as a function of x for the figure (b).

• 5)

A battery of voltage V is connected to 30 W bulb and 60 W bulb as shown in the figure. (a) Identify brightest bulb (b) which bulb has greater resistance?
(c) Suppose the two bulbs are connected in series, which bulb will glow brighter?

#### 12th Standard English Medium Physics Reduced syllabus Five mark important Questions - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

A water molecule has an electric dipole moment of 6.3 × 10-30 Cm. A sample contains 1022 water molecules, with all the dipole moments aligned parallel to the external electric field of magnitude 3 × 105 NC-1. How much work is required to rotate all the water molecules from θ = 00 to 900?

• 2)

A small ball of conducting material having a charge +q and mass m is thrown upward at an angle θ to horizontal surface with an initial speed vo as shown in the figure. There exists an uniform electric field E downward along with the gravitational field g. Calculate the range, maximum height and time of flight in the motion of this charged ball. Neglect the effect of air and treat the ball as a point mass.

• 3)

Suppose a charge +q on Earth’s surface and another +q charge is placed on the surface of the Moon. (a) Calculate the value of q required to balance the gravitational attraction between Earth and Moon (b) Suppose the distance between the Moon and Earth is halved, would the charge q change?
(Take mE = 5.9 × 1024 kg, mM = 7.9 × 1022 kg)

• 4)

A point charge of +10 μC is placed at a distance of 20 cm from another identical point charge of +10 μC. A point charge of -2 μC is moved from point a to b as shown in the figure. Calculate the change in potential energy of the system? Interpret your result.

• 5)

For the given capacitor configuration
(a) Find the charges on each capacitor
(b) potential difference across them
(c) energy stored in each capacitor

#### 12th Standard English Medium Physics Reduced syllabus Three mark important Questions with Answer key - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

Calculate the electrostatic force and gravitational force between the proton and the electron in a hydrogen atom. They are separated by a distance of 5.3 × 10-11 m. The magnitude of charges on the electron and proton are 1.6 × 10-19 C. Mass of the electron is me = 9.1 × 10-31 kg and mass of proton is mp = 1.6 × 10-27 kg.

• 2)

Consider the charge configuration as shown in the figure. Calculate the electric field at point A. If an electron is placed at points A, what is the acceleration experienced by this electron? (mass of the electron = 9.1 × 10-31 kg and charge of electron = −1.6 × 10-19 C)

• 3)

A sample of HCl gas is placed in a uniform electric field of magnitude 3 × 104 NC-1. The dipole moment of each HCl molecule is 3.4 × 10-30 Cm. Calculate the maximum torque experienced by each HCl molecule.

• 4)

Obtain the expression for energy stored in the parallel plate capacitor.

• 5)

Explain in detail how charges are distributed in a conductor, and the principle behind the lightning conductor.

#### 12th Standard English Medium Physics Reduced syllabus Three mark important Questions - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

Calculate the number of electrons in one coulomb of negative charge.

• 2)

Calculate the electrostatic force and gravitational force between the proton and the electron in a hydrogen atom. They are separated by a distance of 5.3 × 10-11 m. The magnitude of charges on the electron and proton are 1.6 × 10-19 C. Mass of the electron is me = 9.1 × 10-31 kg and mass of proton is mp = 1.6 × 10-27 kg.

• 3)

The following pictures depict electric field lines for various charge configurations.

(i) In figure (a) identify the signs of two
charges and find the ratio $\left| \frac { { q }_{ 1 } }{ { q }_{ 2 } } \right|$
(ii) In figure (b), calculate the ratio of two positive charges and identify the strength of the electric field at three points A, B, and C
(iii) Figure (c) represents the electric field lines for three charges. If q2 = -20 nC, then calculate the values of q1 and q3.

• 4)

Define ‘Electric field’ and discuss its various aspects.

• 5)

Obtain an expression for potential energy due to a collection of three point charges which are separated by finite distances.

#### 12th Standard English Medium Physics Reduced syllabus Two mark important Questions with Answer key - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

Define ‘electrostatic potential energy’.

• 2)

What are Non-polar molecules

• 3)

What is dielectric breakdown.

• 4)

What is the electric flux through a cube of side 1cm which encloses on electric dipole?

• 5)

A particle of mass m and charge (-q) enters the region between the two charged plates initrally moving along X-axis with speed Vx as shown in figure. The length of plate is L and an uniform electric field E is maintained between the plates. S.T. vertical deflection of the particle at the far edge of the plate is $\frac { q{ EL }^{ 2 } }{ 2m{ V }_{ x }^{ 2 } }$.

#### 12th Standard English Medium Physics Reduced syllabus Two mark important Questions - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

What is meant by quantisation of charges?

• 2)

Define ‘Electric field’.

• 3)

(i) Two insulated charged copper spheres A & B of identical size have charges qn and -3qA respectively. When they are brought in contact with each other and then separated. What are the new charges on them?
(ii) When third sphere of some size but uncharged is brought in contact with first and then second and finally removed? What are the new charges.

• 4)

A charge Q μc is placed at the centre of a cube what would be the
(i) flux through one face?
(ii) flux passing through two opposite faces of the cube?
Electric flux through whole cube $\frac { Q }{ { \varepsilon }_{ 0 } }$

• 5)

Represent the variation of electric field due to point charge Q with
a) magnitude of charge Q
b) r and
c) $\frac{1}{r^2}$ where r is the distance of the observation point from the charge. graphically.

#### 12th Standard English Medium Physics Reduced syllabus One mark important Questions with Answer key - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 2)

The value of constant 'K' in coulomb law is

• 3)

Two charges are kept at a distance in air what should be the relative permittivity of the medium in which the two charges should be kept at the same distance so that they experience half of the force which they experienced in air?

• 4)

In a parallel plate capacitor of capacitance C, a metal sheet is inserted between the plates, parallel to them. The thickness of the sheet is half of the separation between the plates. The capacitance now becomes

• 5)

During charging a capacitor variation of potential V of the capacitor with time t as shown a

#### 12th Standard English Medium Physics Reduced syllabus One mark important Questions - 2021(Public Exam ) - by Sarojini - Tiruppur - View & Read

• 1)

Two identical point charges of magnitude –q are fi xed as shown in the fi gure below. A third charge +q is placed midway between the two charges at the point P. Suppose this charge +q is displaced a small distance from the point P in the directions indicated by the arrows, in which direction(s) will +q be stable with respect to the displacement

• 2)

An electric dipole is placed at an alignment angle of 300 with an electric fi eld of 2 × 105 NC-1. It experiences a torque equal to 8 N m. Th e charge on the dipole if the dipole length is 1 cm is

• 3)

Four Gaussian surfaces are given below with charges inside each Gaussian surface. Rank the electric fl ux through each Gaussian surface in increasing order.

• 4)

Rank the electrostatic potential energies for the given system of charges in increasing order.

• 5)

If voltage applied on a capacitor is increased from V to 2V, choose the correct conclusion

#### 12th Standard Physics English Medium Recent developments in Physics Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The particle size of ZnO material is 30 nm. Based on the dimension it is classified as

• 2)

The blue print for making ultra durable synthetic material is mimicked from

• 3)

The alloys used for muscle wires in Robots are

• 4)

The technology used for stopping the brain from processing pain is

• 5)

The particle which gives mass to protons and neutrons are

#### 12th Standard Physics English Medium Recent developments in Physics Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The particle size of ZnO material is 30 nm. Based on the dimension it is classified as

• 2)

The blue print for making ultra durable synthetic material is mimicked from

• 3)

The materials used in Robotics are

• 4)

The alloys used for muscle wires in Robots are

• 5)

The technology used for stopping the brain from processing pain is

#### 12th Standard Physics English Medium Electronics and Communication Systems Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Doping a semiconductor results in

• 2)

The output transducer of the communication system converts the radio signal into ________.

• 3)

The forbidden energy band gap in semi conductor, conductor and insulator are E1, E2 and E3 respectively. The relation among them is

• 4)

The radiation of electrical energy is practicable only above _________

• 5)

Microphone converts __________ energy into ________ energy.

#### 12th Standard Physics English Medium Electronics and Communication Systems Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The output transducer of the communication system converts the radio signal into ________.

• 2)

Which of the following is not the advantage of PN junction diode over tube value?

• 3)

In a N-P-N transistor circuit, the emitter, collector and base current are respectively IE, IC and lB. The relation between them is

• 4)

From the follwoing semi-conductor devices _________ operates in forward bias only.

• 5)

To obtain a p-type germanium semiconductor, it must be doped with

#### 12th Standard Physics English Medium Atomic and nuclear Physics Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

In a hydrogen atom, the electron revolving in the fourth orbit, has angular momentum equal to

• 2)

The electric potential between a proton and an electron is given by $V={ V }_{ 0 }in\left( \frac { r }{ { r }_{ 0 } } \right)$, where r0 is a constant. Assume that Bohr atom model is applicable of nth orbit rn with the principal quantum number n is

• 3)

The fig. represents the observed intensity of X-rays emitted by an X-ray tube as a function of wavelength. The sharp peaks A and B denote

• 4)

A beam of electron posses undeflected through mutually perpendicular electric and magnetic fields. If the electric field is switched off and the same magnetic field is maintained, the electrons move,

• 5)

The energy of a photon of characteristic X-ray from a Coolidge tubes comes from

#### 12th Standard Physics English Medium Atomic and nuclear Physics Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Suppose an alpha particle accelerated by a potential of V volt is allowed to collide with a nucleus whose atomic number is Z, then the distance of closest approach of alpha particle to the nucleus is

• 2)

The electric potential between a proton and an electron is given by $V={ V }_{ 0 }in\left( \frac { r }{ { r }_{ 0 } } \right)$, where r0 is a constant. Assume that Bohr atom model is applicable of nth orbit rn with the principal quantum number n is

• 3)

An oil drop carrying a charge q has a mass m kg. It is falling freely in air with terminal speed v. The electric field required to make the drop move upwards with the same speed is

• 4)

When hydrogen atom is in its first excited level, its radius is __________ of the Bohr radius.

• 5)

J.J. Thomson's experiment demonstrated that

#### 12th Standard Physics English Medium Dual Nature of Radiation and Matter Reduced Syllabus Important Questions With Answer Key 20211 - by Sarojini - Tiruppur - View & Read

• 1)

The wavelength λe of an electron and λp of a photon of same energy E are related by

• 2)

If a light of wavelength 330 nm is incident on a metal with work function 3.55 eV, the electrons are emitted. Then the wavelength of the emitted electron is (Take h = 6.6 × 10–34 Js)

• 3)

A photoelectric surface is illuminated successively by monochromatic light of wavelength λ and $\frac{\lambda}{2}.$ If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the fi rst case, the work function at the surface of material is

• 4)

The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV is

• 5)

Emission of electrons by the absorption of heat energy is called_______emission.

#### 12th Standard Physics English Medium Dual Nature of Radiation and Matter Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The wavelength λe of an electron and λp of a photon of same energy E are related by

• 2)

In an electron microscope, the electrons are accelerated by a voltage of 14 kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would

• 3)

A particle of mass 3 × 10–6 g has the same wavelength as an electron moving with a velocity 6 10 × 6m s−1. The velocity of the particle is

• 4)

Photons of wavelength λ are incident on a metal. The most energetic electrons ejected from the metal are bent into a circular arc of radius R by a perpendicular magnetic field having magnitude B. The work function of the metal is

• 5)

The work functions for metals A, B and C are 1.92 eV, 2.0 eV and 5.0 eV respectively. The metals which will emit photoelectrons for a radiation of wavelength 4100$\\ \\ \mathring { A } \\$ is/are

#### 12th Standard Physics English Medium Wave Optics Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

A plane glass is placed over a various coloured letters (violet, green, yellow, red) The letter which appears to be raised more is,

• 2)

In a Young’s double-slit experiment, the slit separation is doubled. To maintain the same fringe spacing on the screen, the screen-to-slit distance D must be changed to,

• 3)

Two coherent monochromatic light beams of intensities I and 4I are superposed. The maximum and minimum possible intensities in the resulting beam are

• 4)

When light is incident on a soap film of thickness 5×10–5 cm, the wavelength of light reflected maximum in the visible region is 5320 Å. Refractive index of the film will be,

• 5)

First diffraction minimum due to a single slit of width 1.0×10–5 cm is at 30o. Then wavelength of light used is,

#### 12th Standard Physics English Medium Wave Optics Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

A plane glass is placed over a various coloured letters (violet, green, yellow, red) The letter which appears to be raised more is,

• 2)

In a Young’s double-slit experiment, the slit separation is doubled. To maintain the same fringe spacing on the screen, the screen-to-slit distance D must be changed to,

• 3)

Two coherent monochromatic light beams of intensities I and 4I are superposed. The maximum and minimum possible intensities in the resulting beam are

• 4)

When light is incident on a soap film of thickness 5×10–5 cm, the wavelength of light reflected maximum in the visible region is 5320 Å. Refractive index of the film will be,

• 5)

First diffraction minimum due to a single slit of width 1.0×10–5 cm is at 30o. Then wavelength of light used is,

#### 12th Standard Physics English Medium Ray Optics Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

An object is placed in front of a convex mirror of focal length of f and the maximum and minimum distance of an object from the mirror such that the image formed is real and magnified.

• 2)

For light incident from air on a slab of refractive index 2, the maximum possible angle of refraction is,

• 3)

A plane glass is placed over a various coloured letters (violet, green, yellow, red) The letter which appears to be raised more is,Two point white dots are 1 mm apart on a black paper. They are viewed by eye of pupil diameter 3 mm approximately. The maximum distance at which these dots can be resolved by the eye is, [take wavelength of light, λ = 500 nm]

• 4)

A light bulb is placed between two mirrors (plane) inclined at an angle of 60°. Number of images formed are

• 5)

A man of length h requires a mirror of length at least equal to, to see his own complete image

#### 12th Standard Physics English Medium Ray Optics Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The speed of light in an isotropic medium depends on,

• 2)

When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index,

• 3)

A ray of light travelling in a transparent medium of refractive index n falls, on a surface separating the medium from air at an angle of incidents of 45o. The ray can undergo total internal reflection for the following n,

• 4)

The light reflected by plane mirror may form a real images.

• 5)

Ray optics is valid, when characteristic dimensions are

#### 12th Standard Physics English Medium Electromagnetic Waves Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

If the magnetic monopole exists, then which of the Maxwell’s equation to be modified?.

• 2)

Who produced the electromagnetic waves first?

• 3)

The existence of E.M. waves was confirmed experimentally by

• 4)

Electromagnetic waves are discovered by

• 5)

Cellular phones use radio frequencies in

#### 12th Standard Physics English Medium Electromagnetic Waves Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

If the magnetic monopole exists, then which of the Maxwell’s equation to be modified?.

• 2)

The phase and orientation of the magnetic vector associated with electromagnetic oscillations differ respectively from those of the corresponding electric vectors by

• 3)

Which one of the following is not an electromagnetic waves?

• 4)

Calcium or Barium salts in bunsen flame, CO2, N2 molecule, NH3 gas in a discharge tube gives_______.

• 5)

__________discovered electromagnetic induction.

#### 12th Standard Physics English Medium Electromagnetic Induction and Alternating Current Reduced Syllabus Important Questions With Answer Key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

When the current changes from +2A to −2A in 0.05 s, an emf of 8 V is induced in a coil. Th e co-efficient of self-induction of the coil is

• 2)

A circular coil with a cross-sectional area of 4 cm2 has 10 turns. It is placed at the centre of a long solenoid that has 15 turns/cm and a cross-sectional area of 10 cm2. The axis of the coil coincides with the axis of the solenoid. What is their mutual inductance?

• 3)

In a transformer, the number of turns in the primary and the secondary are 410 and 1230 respectively. If the current in primary is 6A, then that in the secondary coil is

• 4)

In a series resonant RLC circuit, the voltage across 100 Ω resistor is 40 V. The resonant frequency ω is 250 rad/s. If the value of C is 4 μF, then the voltage across L is

• 5)

In an oscillating LC circuit, the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electric and magnetic fields is

#### 12th Standard Physics English Medium Electromagnetic Induction and Alternating Current Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

An electron moves on a straight line path XY as shown in the figure. The coil abcd is adjacent to the path of the electron. What will be the direction of current, if any, induced in the coil?

• 2)

When the current changes from +2A to −2A in 0.05 s, an emf of 8 V is induced in a coil. Th e co-efficient of self-induction of the coil is

• 3)

In a transformer, the number of turns in the primary and the secondary are 410 and 1230 respectively. If the current in primary is 6A, then that in the secondary coil is

• 4)

An emf of 12V is induced when the current in the coil changes at the rate of 40 A S-1. The coefficient of self induction of the coil is

• 5)

Transformer works on

#### 12th Standard Physics English Medium Magnetism and Magnetic Effects of Electric Current Reduced Syllabus Important Questions with Answer key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Th e force experienced by a particle having mass m and charge q accelerated through a potential diff erence V when it is kept under perpendicular magnetic field $\vec { B }$ is

• 2)

Th ree wires of equal lengths are bent in the form of loops. One of the loops is circle, another is a semi-circle and the third one is a square. Th ey are placed in a uniform magnetic fi eld and same electric current is passed through them. Which of the following loop confi guration will experience greater torque ?

• 3)

A wire of length l carries a current I along the Y direction and magnetic field is given by $\vec { B } =\frac { \beta }{ \sqrt { 3 } } =(\hat { i } +\hat { j } +\hat { k } )T.$ The magnitude of Lorentz force acting on the wire is

• 4)

Direction of magnetic force on a positive charge moving in a magnetic field is given by

• 5)

Consider the motion of a charged particle in a uniform magnetic field directed into the paper. If velocity v of the particle is in the plane of the paper, the charged particle will describe a

#### 12th Standard Physics English Medium Magnetism and Magnetic Effects of Electric Current Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The magnetic fi eld at the center O of the following current loop is

• 2)

An electron moves straight inside a charged parallel plate capacitor of uniform charge density σ. Th e time taken by the electron to cross the parallel plate capacitor when the plates of the capacitor are kept under constant magnetic fi eld of induction $\vec { B }$is

• 3)

Th ree wires of equal lengths are bent in the form of loops. One of the loops is circle, another is a semi-circle and the third one is a square. Th ey are placed in a uniform magnetic fi eld and same electric current is passed through them. Which of the following loop confi guration will experience greater torque ?

• 4)

A wire of length l carries a current I along the Y direction and magnetic field is given by $\vec { B } =\frac { \beta }{ \sqrt { 3 } } =(\hat { i } +\hat { j } +\hat { k } )T.$ The magnitude of Lorentz force acting on the wire is

• 5)

The BH curve for a ferromagnetic material is shown in the figure. The material is placed inside a long solenoid which contains 1000 turns/cm. The current that should be passed in the solenonid to demagnetize the ferromagnet completely is

#### 12th Standard Physics English Medium Current Electricity Reduced Syllabus Important Questions with Answer key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

A wire connected to a power supply of 230 V has power dissipation P1. Suppose the wire is cut into two equal pieces and connected parallel to the same power supply. In this case power dissipation is P2. The ratio $\frac{P_2}{P_1}$ is

• 2)

In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be

• 3)

When 'n' resistors of equal resistance (R) are connected in series and in parallel respectively,then the ratio of their effective resistance is

• 4)

A potential difference is applied an the ends of a metallic wire. If the potential difference is doubled, the drift velocity

• 5)

A bird sitting on an insulated wire carrying a current feels quite safe because

#### 12th Standard Physics English Medium Current Electricity Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

There is a current of 1.0 A in the circuit shown below. What is the resistance of P ?

• 2)

When 'n' resistors of equal resistance (R) are connected in series and in parallel respectively,then the ratio of their effective resistance is

• 3)

An unknown resistance is connected in parallel with a 15$\Omega$ resistance and a 12V battery. What is the value of the unknown resistance if the current in the circuit is 2A?

• 4)

Kirchoff's I law i.e, $\Sigma i=0$ at a junction, deals with the conservation of

• 5)

Resistance increases with increases in temperature for

#### 12th Standard Physics English Medium Electrostatics Reduced Syllabus Important Questions with Answer key 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Which charge configuration produces a uniform electric field?

• 2)

The total electric fl ux for the following closed surface which is kept inside water

• 3)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 4)

In electrostatics if the charges are in motion, another force named __________ comes into play in addition to coulomb force

• 5)

_______ and Coulomb's law form fundamental principles of electrostatics

#### 12th Standard Physics English Medium Electrostatics Reduced Syllabus Important Questions 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Which charge configuration produces a uniform electric field?

• 2)

The total electric fl ux for the following closed surface which is kept inside water

• 3)

_______ and Coulomb's law form fundamental principles of electrostatics

• 4)

A force of 40 N is acting between two charges in air if the space between then is filled with glass εr = 8. Then the force between then is

• 5)

The expression for electric field in vector form is

#### 12th Standard Physics English Medium Reduced Syllabus Model Question paper with answer key - 2021 Part - 2 - by Sarojini - Tiruppur - View & Read

• 1)

Two identical point charges of magnitude –q are fi xed as shown in the fi gure below. A third charge +q is placed midway between the two charges at the point P. Suppose this charge +q is displaced a small distance from the point P in the directions indicated by the arrows, in which direction(s) will +q be stable with respect to the displacement

• 2)

The total electric fl ux for the following closed surface which is kept inside water

• 3)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 4)

The figure shows tow parallel equipotential surface A and B kept at a small distance 'r' a part from each other. A point change of Q coulomb is taken from the surface A to B. The amount of net work done will be

• 5)

During charging a capacitor variation of potential V of the capacitor with time t as shown a

#### 12th Standard Physics English Medium Reduced Syllabus Model Question paper with answer key - 2021 Part - 1 - by Sarojini - Tiruppur - View & Read

• 1)

An electric dipole is placed at an alignment angle of 300 with an electric fi eld of 2 × 105 NC-1. It experiences a torque equal to 8 N m. Th e charge on the dipole if the dipole length is 1 cm is

• 2)

Two identical conducting balls having positive charges q1 and q2 are separated by a center to center distance r. If they are made to touch each other and then separated to the same distance, the force between them will be

• 3)

Two identical coils, each with N turns and radius R are placed coaxially at a distance R as shown in the fi gure. If I is the current passing through the loops in the same direction, then the magnetic field at a point P which is at exactly at$\frac { R }{ 2 }$ distance between two coils is

• 4)

A thin semi-circular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic fi eld B, as shown in the fi gure.

The potential diff erence developed across the ring when its speed v, is

• 5)

An inductor 20 mH, a capacitor 50 μF and a resistor 40 Ω are connected in series across a source of emf v = 10 sin 340 t. The power loss in AC circuit is

#### 12th Standard Physics English Medium Reduced Syllabus Model Question paper - 2021 Part - 2 - by Sarojini - Tiruppur - View & Read

• 1)

• 2)

Two short bar magnets have magnetic moments 1.20 Am2 and 1.00 Am2 respectively. They are kept on a horizontal table parallel to each other with their north poles pointing towards the south. They have a common magnetic equator and are separated by a distance of 20.0 cm. The value of the resultant horizontal magnetic induction at the mid-point O of the line joining their centers is (Horizontal components of Earth’s magnetic induction is 3.6 x 10-5 Wb m-2 )

• 3)

Th e electrical series circuit in digital form is

• 4)

A current gain for, a transistor working as CB amplifier is 0.90. If emitter current is 10 mA, then base current is

• 5)

Digital circuits can be made to be respective use of:

#### 12th Standard Physics English Medium Reduced Syllabus Model Question paper - 2021 Part - 1 - by Sarojini - Tiruppur - View & Read

• 1)

An uncharged metal sphere is placed between two equal and oppositely charged metal plates. The nature of lines of force will be

• 2)

In three phase AC generator the three coils are fastened rigidly together and are displaced from each other by an angle

• 3)

In an a.c. circuit with an inductor

• 4)

In a LCR series a.c, circuit, the phase difference between current and voltage is 60°. If the net reactance of the circuit is 17.32Ω, the value of the resistance is

• 5)

Which of the following is used to study crystal structure?

#### 12th Standard Physics English Medium Reduced Syllabus Important Questions with Answer key - 2021 Part - 2 - by Sarojini - Tiruppur - View & Read

• 1)

What physical quantities may X and Y represent? [Y represents the first mentioned quantity].

• 2)

Which one of the following pair of particles move with same velocity along the same circular path in a uniform magnetic field?

• 3)

This works on the principle of Tangent Law

• 4)

An α-particle enters a magnetic field of 1T with a velocity 106 m/s in a direction perpendicular to the field. The force on α-particle is

• 5)

Which of the following electromagnetic radiation is used for viewing objects through fog

#### 12th Standard Physics English Medium Reduced Syllabus Important Questions with Answer key - 2021 Part - 1 - by Sarojini - Tiruppur - View & Read

• 1)

By using law of conservation of electric charge balance the following equations:
92U238 90Th234 ________.

• 2)

There is a current of 1.0 A in the circuit shown below. What is the resistance of P ?

• 3)

An unknown resistance is connected in parallel with a 15$\Omega$ resistance and a 12V battery. What is the value of the unknown resistance if the current in the circuit is 2A?

• 4)

The instantaneous values of alternating current and voltage in a circuit are $i=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t \right)$ A and v=$=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t+\frac { \pi }{ 3 } \right) V.$The average power in watts consumed in the circuit is

• 5)

Lenz's law is in accordance with the law of

#### 12th Standard Physics English Medium Reduced Syllabus Important Questions - 2021 Part - 2 - by Sarojini - Tiruppur - View & Read

• 1)

The internal resistance of a 2.1 V cell which gives a current of 0.2 A through a resistance of 10 Ω is

• 2)

The emf of a battery is 3 volts and internal resistance 0.125 $\Omega$ . The difference of potential
at the terminal of battery when connected across an external resistance of 1 $\Omega$ is

• 3)

Peltier effect is the converse of

• 4)

Kirchoff's II law isa consequence of conservation of________

• 5)

Which one of the following is correct. According to Biot-Savart law, the magnetic induction is directly proportional to

#### 12th Standard Physics English Medium Reduced Syllabus Important Questions - 2021 Part - 1 - by Sarojini - Tiruppur - View & Read

• 1)

Which charge configuration produces a uniform electric field?

• 2)

An electric dipole is placed at an alignment angle of 300 with an electric fi eld of 2 × 105 NC-1. It experiences a torque equal to 8 N m. Th e charge on the dipole if the dipole length is 1 cm is

• 3)

The total electric fl ux for the following closed surface which is kept inside water

• 4)

The electric field created by a _________ is basically a non-uniform electric field.

• 5)

The unit for electric susceptibility is

#### 12th Standard Physics Recent Developments in Physics English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Which one of the following is the natural nanomaterial

• 2)

The method of making nanomaterial by assembling the atoms is called

• 3)

The materials used in Robotics are

• 4)

The technology used for stopping the brain from processing pain is

• 5)

The gravitational waves were theoretically proposed by

#### 12st Standard Physics Recent Developments in Physics English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The particle size of ZnO material is 30 nm. Based on the dimension it is classified as

• 2)

The blue print for making ultra durable synthetic material is mimicked from

• 3)

The alloys used for muscle wires in Robots are

• 4)

The particle which gives mass to protons and neutrons are

• 5)

__________ Scanning Electron Micrograph (SEM) showing the nano structures on the surface of a leaf from a lotus plant

#### 12th Standard Physics Communication Systems English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The signal is aff ected by noise in a communication system

• 2)

The internationally accepted frequency deviation for the purpose of FM broadcasts

• 3)

The loss of strengh of a signal while propagating through a medium is known as_________.

• 4)

Modulation is the process of superposing

• 5)

Large band width for higher data is achieved by using

#### 12th Standard Physics Communication Systems English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The output transducer of the communication system converts the radio signal into ________.

• 2)

The variation of frequency of carrier wave with respect to the amplitude of the modulating signal is called _______.

• 3)

The frequency range of 3 MHz to 30 MHz is used for

• 4)

All medium wave signals received during day time use __________ wave propagation

• 5)

The radiowaves after refraction from different part of ionosphere on reaching the earth are called as

#### 12th Standard Physics Semiconductor Electronics English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Doping a semiconductor results in

• 2)

When a transistor is fully switched on, it is said to be

• 3)

Th e electrical series circuit in digital form is

• 4)

By adding _________ impurity in intrinsic semi conductor, p type semiconductor is made. Charge of these p type semiconductoris ____________

• 5)

The behaviour of Ge as semi-conductor is due to width of:

#### 12th Standard Physics Semiconductor Electronics English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The barrier potential of a silicon diode is approximately

• 2)

The primary use of a zener diode is

• 3)

The light emitted in an LED is due to

• 4)

The specific characteristic of a common emitter amplifier is

• 5)

If the input to the NOT gate is A = 1011, its output is

#### 12th Standard Physics Atomic and Nuclear physics English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

In a hydrogen atom, the electron revolving in the fourth orbit, has angular momentum equal to

• 2)

The electric potential between a proton and an electron is given by $V={ V }_{ 0 }in\left( \frac { r }{ { r }_{ 0 } } \right)$, where r0 is a constant. Assume that Bohr atom model is applicable of nth orbit rn with the principal quantum number n is

• 3)

The nucleus is approximately spherical in shape. Then the surface area of nucleus having mass number A varies as

• 4)

The half-life period of a radioactive element A is same as the mean life time of another radioactive element B. Initially both have the same number of atoms. Then

• 5)

The circumference of an electron's orbit of radius r must be an integral multiple of de Broglie wavelength that is

#### 12th Standard Physics Atomic and Nuclear physics English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Suppose an alpha particle accelerated by a potential of V volt is allowed to collide with a nucleus whose atomic number is Z, then the distance of closest approach of alpha particle to the nucleus is

• 2)

The ratio of the wavelengths for the transition from n=2 to n=1 in Li++, He+ and H is

• 3)

the nuclear radius of 27 al is 3.6 fermi, the approximate nuclear radius of 64Cu is

• 4)

A radioactive nucleus (initial mass number A and atomic number Z) emits 2α and 2 positrons. The ratio of number of neutrons to that of proton in the final nucleus will be

• 5)

A system consists of N0 nucleus at t=0. The number of nuclei remaining after half of a half-life (that is, at time t=$\frac{q}{2}T_\frac{1}{2}$)

#### 12th Standard Physics Dual Nature of Radiation and Matter English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

In an electron microscope, the electrons are accelerated by a voltage of 14 kV. If the voltage is changed to 224 kV, then the de Broglie wavelength associated with the electrons would

• 2)

Two radiations with photon energies 0.9 eV and 3.3 eV respectively are falling on a metallic surface successively. If the work function of the metal is 0.6 eV, then the ratio of maximum speeds of emitted electrons will be

• 3)

The mean wavelength of light from sun is taken to be 550 nm and its mean power is 3.8 × 1026W. The number of photons received by the human eye per second on the average from sunlight is of the order of

• 4)

The work functions for metals A, B and C are 1.92 eV, 2.0 eV and 5.0 eV respectively. The metals which will emit photoelectrons for a radiation of wavelength 4100$\\ \\ \mathring { A } \\$ is/are

• 5)

The work function of a metal is hvo' Light of frequency v falls on this metal. The photoelectric effect will take: place only if

#### 12th Standard Physics Dual Nature of Radiation and Matter English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The wavelength λe of an electron and λp of a photon of same energy E are related by

• 2)

A light source of wavelength 520 nm emits 1.04 × 1015 photons per second while the second source of 460 nm produces 1.38 × 1015 photons per second. Then the ratio of power of second source to that of first source is

• 3)

Photons of wavelength λ are incident on a metal. The most energetic electrons ejected from the metal are bent into a circular arc of radius R by a perpendicular magnetic field having magnitude B. The work function of the metal is

• 4)

Emission of electrons by the absorption of heat energy is called_______emission.

• 5)

P and E denote the linear momentum and energy of a photon. If the wavelength is decreased

#### 12th Standard Physics Optics English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

A rod of length 10 cm lies along the principal axis of a concave mirror of focal length 10 cm in such a way that its end closer to the pole is 20 cm away from the mirror. The length of the image is,

• 2)

The radius of curvature of curved surface at a thin planoconvex lens is 10 cm and the refractive index is 1.5. If the plane surface is silvered, then the focal length will be,

• 3)

Two coherent monochromatic light beams of intensities I and 4I are superposed. The maximum and minimum possible intensities in the resulting beam are

• 4)

First diffraction minimum due to a single slit of width 1.0×10–5 cm is at 30o. Then wavelength of light used is,

• 5)

One of the of Young’s double slits is covered with a glass plate as shown in figure. The position of central maximum will,

#### 12th Standard Physics Optics English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The speed of light in an isotropic medium depends on,

• 2)

An object is placed in front of a convex mirror of focal length of f and the maximum and minimum distance of an object from the mirror such that the image formed is real and magnified.

• 3)

When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index,

• 4)

An air bubble in glass slab of refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness of the slab is,

• 5)

A plane glass is placed over a various coloured letters (violet, green, yellow, red) The letter which appears to be raised more is,

#### 12th Standard Physics Electromagnetic Waves English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

If the amplitude of the magnetic fi eld is 3 × 10−6 T, then amplitude of the electric fi eld for a electromagnetic waves is

• 2)

Th e electric and the magnetic field, associated with an electromagnetic wave, propagating along X axis can be represented by

• 3)

A radiation of energy E falls normally on a perfectly refl ecting surface. Th e momentum transferred to the surface

• 4)

Which one of them is used to produce a propagating electromagnetic wave?.

• 5)

Which of the following is NOT true for electromagnetic waves?

#### 12th Standard Physics Electromagnetic Waves English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The dimension of $\frac { 1 }{ { \mu }_{ 0 }{ \varepsilon }_{ 0 } }$ is

• 2)

Which of the following electromagnetic radiation is used for viewing objects through fog

• 3)

If the magnetic monopole exists, then which of the Maxwell’s equation to be modified?.

• 4)

Which of the following is an electromagnetic wave?

• 5)

Let E = Eo sin[106 x -ωt] be the electric field of plane electromagnetic wave, the value of ω is

#### 12th Standard Physics Electromagnetic Induction and Alternating Current English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

When the current changes from +2A to −2A in 0.05 s, an emf of 8 V is induced in a coil. Th e co-efficient of self-induction of the coil is

• 2)

A circular coil with a cross-sectional area of 4 cm2 has 10 turns. It is placed at the centre of a long solenoid that has 15 turns/cm and a cross-sectional area of 10 cm2. The axis of the coil coincides with the axis of the solenoid. What is their mutual inductance?

• 3)

In a series RL circuit, the resistance and inductive reactance are the same. Then the phase difference between the voltage and current in the circuit is

• 4)

An inductor 20 mH, a capacitor 50 μF and a resistor 40 Ω are connected in series across a source of emf v = 10 sin 340 t. The power loss in AC circuit is

• 5)

Lenz's law is in accordance with the law of

#### 12th Standard Physics Electromagnetic Induction and Alternating Current English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

An electron moves on a straight line path XY as shown in the figure. The coil abcd is adjacent to the path of the electron. What will be the direction of current, if any, induced in the coil?

• 2)

Th e fl ux linked with a coil at any instant t is given by $\Phi$B =10t2−50t+ 250 . The induced emf at t = 3s is

• 3)

In a transformer, the number of turns in the primary and the secondary are 410 and 1230 respectively. If the current in primary is 6A, then that in the secondary coil is

• 4)

The instantaneous values of alternating current and voltage in a circuit are $i=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t \right)$ A and v=$=\frac { 1 }{ \sqrt { 2 } } sin\left( 100\pi t+\frac { \pi }{ 3 } \right) V.$The average power in watts consumed in the circuit is

• 5)

Electromagnetic induction is-not used in

#### 12th Standard Physics Magnetism and magnetic effects of electric current English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

An electron moves straight inside a charged parallel plate capacitor of uniform charge density σ. Th e time taken by the electron to cross the parallel plate capacitor when the plates of the capacitor are kept under constant magnetic fi eld of induction $\vec { B }$is

• 2)

A wire of length l carries a current I along the Y direction and magnetic field is given by $\vec { B } =\frac { \beta }{ \sqrt { 3 } } =(\hat { i } +\hat { j } +\hat { k } )T.$ The magnitude of Lorentz force acting on the wire is

• 3)

A non-conducting charged ring of charge q, mass m and radius r is rotated with constant angular speed ω. Find the ratio of its magnetic moment with angular momentum is

• 4)

A flat dielectric disc of radius R carries an excess charge on its surface. The surface charge density is σ. The disc rotates about an axis perpendicular to its plane passing through the center with angular velocity ω. Find the magnitude of the torque on the disc if it is placed in a uniform magnetic field whose strength is B which is directed perpendicular to the axis of rotation

• 5)

In a thermocouple, the temperature of cold junction is 30°C and the neutral temperature is 310°C. The temperature of inversion is

#### 12th Standard Physics Magnetism and magnetic effects of electric current English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

The magnetic fi eld at the center O of the following current loop is

• 2)

Th e force experienced by a particle having mass m and charge q accelerated through a potential diff erence V when it is kept under perpendicular magnetic field $\vec { B }$ is

• 3)

A thin insulated wire forms a plane spiral of N = 100 tight turns carrying a current I = 8 m A (milli ampere). The radii of inside and outside turns are a = 50 mm and b = 100 mm respectively.
The magnetic induction at the center of the spiral is

• 4)

A bar magnet of length l and magnetic moment M is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be

• 5)

The BH curve for a ferromagnetic material is shown in the figure. The material is placed inside a long solenoid which contains 1000 turns/cm. The current that should be passed in the solenonid to demagnetize the ferromagnet completely is

#### 12th Standard Physics Current Electricity English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

A wire of resistance 2 ohms per meter is bent to form a circle of radius 1m. Th e equivalent resistance between its two diametrically opposite points, A and B as shown in the fi gure is

• 2)

A carbon resistor of (47 ± 4.7 ) k Ω to be marked with rings of diff erent colours for its identifi cation. Th e colour code sequence will be

• 3)

There is a current of 1.0 A in the circuit shown below. What is the resistance of P ?

• 4)

The temperature coefficient of resistance of a wire is 0.00125 per °C. At 300 K, its resistance is 1 Ω. The resistance of the wire will be 2 Ω at

• 5)

The electrical resistivity of a thin copper wire and a thick copper wire are respectively ${ P }_{ 1 }\Omega$ m and ${ P }_{ 2 }\Omega$ m Then.

#### 12th Standard Physics Current Electricity English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Th e following graph shows current versus voltage values of some unknown conductor. What is the resistance of this conductor?

• 2)

A toaster operating at 240 V has a resistance of 120 Ω. Th e power is

• 3)

What is the value of resistance of the following resistor?

• 4)

A wire connected to a power supply of 230 V has power dissipation P1. Suppose the wire is cut into two equal pieces and connected parallel to the same power supply. In this case power dissipation is P2. The ratio $\frac{P_2}{P_1}$ is

• 5)

In a large building, there are 15 bulbs of 40W, 5 bulbs of 100W, 5 fans of 80W and 1 heater of 1kW are connected. The voltage of electric mains is 220V. The minimum capacity of the main fuse of the building will be

#### 12th Standard Physics Electrostatics English Medium Free Online Test One Mark questions with Answer Key 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

What is the ratio of the charges $\left| \frac { { q }_{ 1 } }{ { q }_{ 2 } } \right|$ for the following electric field line pattern?

• 2)

Four Gaussian surfaces are given below with charges inside each Gaussian surface. Rank the electric fl ux through each Gaussian surface in increasing order.

• 3)

The total electric fl ux for the following closed surface which is kept inside water

• 4)

Rank the electrostatic potential energies for the given system of charges in increasing order.

• 5)

Three capacitors are connected in triangle as shown in the figure. The equivalent capacitance between the points A and C is

#### 12th Standard Physics Electrostatics English Medium Free Online Test One Mark questions 2020 - 2021 - by Sarojini - Tiruppur - View & Read

• 1)

Which charge configuration produces a uniform electric field?

• 2)

A thin conducting spherical shell of radius R has a charge Q which is uniformly distributed on its surface. The correct plot for electrostatic potential due to this spherical shell is

• 3)

Three capacitors are connected in triangle as shown in the figure. The equivalent capacitance between the points A and C is

• 4)

In a hydrogen atom the electron revolves around the proton in an orbit of 0.53 $\mathring { A }$. The potential produced by the electron on the nuleus is

• 5)

The electric field created by a _________ is basically a non-uniform electric field.

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Ten - by Sarojini - Tiruppur - View & Read

• 1)

If voltage applied on a capacitor is increased from V to 2V, choose the correct conclusion

• 2)

The electric field created by a _________ is basically a non-uniform electric field.

• 3)

Which of the following cannot be the units of electric field intensity?

• 4)

A wire of resistance 2 ohms per meter is bent to form a circle of radius 1m. Th e equivalent resistance between its two diametrically opposite points, A and B as shown in the fi gure is

• 5)

Temperature co-effieient of resistance for metals is

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Ten - by Sarojini - Tiruppur - View & Read

• 1)

Two points A and B are maintained at a potential of 7 V and -4 V respectively. The work done in moving 50 electrons from A to B is

• 2)

The time taken by a conductor to reach electrostatic equilibrium is in the order of

• 3)

The force between like charges is _________.

• 4)

A carbon resistor of (47 ± 4.7 ) k Ω to be marked with rings of diff erent colours for its identifi cation. Th e colour code sequence will be

• 5)

The equivalent resistance between A and Bin the figure is

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Nine - by Sarojini - Tiruppur - View & Read

• 1)

Two identical conducting balls having positive charges q1 and q2 are separated by a center to center distance r. If they are made to touch each other and then separated to the same distance, the force between them will be

• 2)

A parallel plate capacitor stores a charge Q at a voltage V. Suppose the area of the parallel plate capacitor and the distance between the plates are each doubled then which is the quantity that will change?

• 3)

What physical quantities may X and Y represent? [Y represents the first mentioned quantity].

• 4)

The electric flux is ________ if the electric field lines enter the closed surface.

• 5)

In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Nine - by Sarojini - Tiruppur - View & Read

• 1)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 2)

In electrostatics if the charges are in motion, another force named __________ comes into play in addition to coulomb force

• 3)

Van de Graaff generator produces an electrostatic potential difference of_______ volts.

• 4)

When a point charge of 6mC is moved between two points in an electric field, the work done is 1.8 x 10-5 J. The potential difference between the two points is

• 5)

Near a charged object A another earthed object B is placed. Charges are induced on B. If B is removed. After that the charge on A ________.

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Eight - by Sarojini - Tiruppur - View & Read

• 1)

If voltage applied on a capacitor is increased from V to 2V, choose the correct conclusion

• 2)

Two charged bodies of charges +q, -3q are brought in contact and separated. The charges prossed by each body after separation.

• 3)

A carbon resistor of (47 ± 4.7 ) k Ω to be marked with rings of diff erent colours for its identifi cation. Th e colour code sequence will be

• 4)

The internal resistance of a 2.1 V cell which gives a current of 0.2 A through a resistance of 10 Ω is

• 5)

The temperature coefficient of resistance is positive__________.

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Eight - by Sarojini - Tiruppur - View & Read

• 1)

Three capacitors are connected in triangle as shown in the figure. The equivalent capacitance between the points A and C is

• 2)

What will happen if two conducting spheres are separately charged and then brought in contact?

• 3)

During charging a capacitor variation of potential V of the capacitor with time t as shown a

• 4)

The total dipole moment per unit volume of the dielectric is________.

• 5)

The repulsive force between two like charges of 1 coulomb each separated by a distance of 1 m in vacuum is equal to :

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Seven - by Sarojini - Tiruppur - View & Read

• 1)

Two identical conducting balls having positive charges q1 and q2 are separated by a center to center distance r. If they are made to touch each other and then separated to the same distance, the force between them will be

• 2)

A non-conducting material which has no free electrons is called

• 3)

The electric flux through a surface will be minimum when the angle between Eand A is

• 4)

Charge Q on a capacitor varies with voltage Vas shown in graph, where Q is along X-axis and V along Y-axis. The area of triangle OAB represents

• 5)

A Gaussian surface in the figure is shown by dotted line. The electric field on the surface will be

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Seven - by Sarojini - Tiruppur - View & Read

• 1)

A parallel plate capacitor stores a charge Q at a voltage V. Suppose the area of the parallel plate capacitor and the distance between the plates are each doubled then which is the quantity that will change?

• 2)

The value of constant 'K' in coulomb law is

• 3)

Four plates each of area 'N. and inferplate separation 'd' are placed as shown in figure. The two inner plates are connected to the point 'B' and outer to point 'A'. What is equivalent capacitance?

• 4)

A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of

• 5)

Which of the following has negative temperature coefficient of resistance?

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Six - by Sarojini - Tiruppur - View & Read

• 1)

A thin conducting spherical shell of radius R has a charge Q which is uniformly distributed on its surface. The correct plot for electrostatic potential due to this spherical shell is

• 2)

Charge Q on a capacitor varies with voltage Vas shown in graph, where Q is along X-axis and V along Y-axis. The area of triangle OAB represents

• 3)

When an electric dipole is placed in a uniform external electric field parallel to the field, it will experience_________.

• 4)

A wire of resistance 2 ohms per meter is bent to form a circle of radius 1m. Th e equivalent resistance between its two diametrically opposite points, A and B as shown in the fi gure is

• 5)

Four resistances are connected to a 5V battery of negligible internal resistance as shown what is the potential across $2\Omega$?

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Six - by Sarojini - Tiruppur - View & Read

• 1)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 2)

Based on Franklin's convention amber rods are_________.

• 3)

The direction of electric field at a point the equatorial line due to an electric dipole is

• 4)

A carbon resistor of (47 ± 4.7 ) k Ω to be marked with rings of diff erent colours for its identifi cation. Th e colour code sequence will be

• 5)

A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Five - by Sarojini - Tiruppur - View & Read

• 1)

An electric dipole is placed at an alignment angle of 300 with an electric fi eld of 2 × 105 NC-1. It experiences a torque equal to 8 N m. Th e charge on the dipole if the dipole length is 1 cm is

• 2)

An isolated metal sphere of radius 'r' is given a charge' q'. The potential energy of the sphere is

• 3)

The expression for electric potentid difference is

• 4)

Torque experienced by a dipole in an electric field when it is placed parallel to the field is ______.

• 5)

What is the current out of the battery?

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Five - by Sarojini - Tiruppur - View & Read

• 1)

Rank the electrostatic potential energies for the given system of charges in increasing order.

• 2)

A positively charged body 'A' has been brought near a brass cylinder 'B' mounted on a glass stand as shown in the figure. The potential of 'B' will be

• 3)

What physical quantities may X and Y represent? [Y represents the first mentioned quantity].

• 4)

Electrostatics deals with the _________

• 5)

In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be

#### 12th Standard Physics English Medium Free Online Test One Mark Questions with Answer Key 2020 - Part Four - by Sarojini - Tiruppur - View & Read

• 1)

A thin conducting spherical shell of radius R has a charge Q which is uniformly distributed on its surface. The correct plot for electrostatic potential due to this spherical shell is

• 2)

The given figure is a plot of lines of force due to two charges q1 & q2 find out the sign of charges

• 3)

A wire connected to a power supply of 230 V has power dissipation P1. Suppose the wire is cut into two equal pieces and connected parallel to the same power supply. In this case power dissipation is P2. The ratio $\frac{P_2}{P_1}$ is

• 4)

In the case of Wheatstone)s Bridge) the bridge balance condition will be obtained only when____

• 5)

Two short bar magnets have magnetic moments 1.20 Am2 and 1.00 Am2 respectively. They are kept on a horizontal table parallel to each other with their north poles pointing towards the south. They have a common magnetic equator and are separated by a distance of 20.0 cm. The value of the resultant horizontal magnetic induction at the mid-point O of the line joining their centers is (Horizontal components of Earth’s magnetic induction is 3.6 x 10-5 Wb m-2 )

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Four - by Sarojini - Tiruppur - View & Read

• 1)

If voltage applied on a capacitor is increased from V to 2V, choose the correct conclusion

• 2)

A force of 40 N is acting between two charges in air if the space between then is filled with glass εr = 8. Then the force between then is

• 3)

Two copper spheres A and B of same size are charged to same potential. A is hollow and B is solid. Which of the two holds more charge?

• 4)

Which graph shows the variation of electric field E due to a hollow spherical conductor of radius R as a function of distance from the centre of the sphere?

• 5)

A closed system contains four charges -8.1C, 14.6C, 20.2C and -200 mC. The total charge in the system_______.

#### 12th Standard Physics English Medium Free Online Test one mark questions with answer key 2020 - Part Three - by Sarojini - Tiruppur - View & Read

• 1)

An electric field $\vec { E } =10x\hat { i }$ exists in a certain region of space. Then the potential difference V = Vo – VA, where Vo is the potential at the origin and VA is the potential at x = 2 m is:

• 2)

Charge per unit volume is called

• 3)

The negative gradient of potential is

• 4)

A charge QμC is placed at the center of a cube. The flux coming out from any surface will be

• 5)

Surface density of charge on a sphere of radius R in terms of electric intensity E at a distance r in free space is

#### 12th Standard Physics English Medium Free Online Test 1 mark questions 2020 - Part Three - by Sarojini - Tiruppur - View & Read

• 1)

Four Gaussian surfaces are given below with charges inside each Gaussian surface. Rank the electric fl ux through each Gaussian surface in increasing order.

• 2)

In a parallel plate capacitor of capacitance C, a metal sheet is inserted between the plates, parallel to them. The thickness of the sheet is half of the separation between the plates. The capacitance now becomes

• 3)

In a hollow spherical shell potential (V) changes with respect to distance (r) from centre.
$\left[ { V }_{ inside }=\frac { Q }{ 4\pi { \varepsilon }_{ 0 }R } r\le R,\quad { V }_{ outside }=\frac { Q }{ 4\pi { \varepsilon }_{ 0 }r } r\ge R,V\alpha \frac { 1 }{ r } \right]$

• 4)

Two wires of A and B with circular cross section made up of the same material with equal lengths. Suppose RA = 3 RB, then what is the ratio of radius of wire A to that of B?

• 5)

When the free electrons are moving in all possible directions, the value of the current produced is_______

#### 12th Standard Physics English Medium Free Online Test Book Back 1 Mark Questions with Answer Key - Part Three - by Sarojini - Tiruppur - View & Read

• 1)

Two points A and B are maintained at a potential of 7 V and -4 V respectively. The work done in moving 50 electrons from A to B is

• 2)

In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60W bulb for use in India is R, the resistance of a 60W bulb for use in USA will be

• 3)

A non-conducting charged ring of charge q, mass m and radius r is rotated with constant angular speed ω. Find the ratio of its magnetic moment with angular momentum is

• 4)

Th e current i fl owing in a coil varies with time as shown in the fi gure. Th e variation of induced emf with time would be

• 5)

Consider an oscillator which has a charged particle and oscillates about its mean position with a frequency of 300 MHz. Th e wavelength of electromagnetic waves produced by this oscillator is

#### 12th Standard Physics English Medium Free Online Test Book Back One Mark Questions - Part Three - by Sarojini - Tiruppur - View & Read

• 1)

The total electric fl ux for the following closed surface which is kept inside water

• 2)

Th e following graph shows current versus voltage values of some unknown conductor. What is the resistance of this conductor?

• 3)

A thin insulated wire forms a plane spiral of N = 100 tight turns carrying a current I = 8 m A (milli ampere). The radii of inside and outside turns are a = 50 mm and b = 100 mm respectively.
The magnetic induction at the center of the spiral is

• 4)

Th e fl ux linked with a coil at any instant t is given by $\Phi$B =10t2−50t+ 250 . The induced emf at t = 3s is

• 5)

Consider an oscillator which has a charged particle and oscillates about its mean position with a frequency of 300 MHz. Th e wavelength of electromagnetic waves produced by this oscillator is

#### 12th Standard Physics English Medium Free Online Test Book Back 1 Mark questions with Answer Key - Part Two - by Sarojini - Tiruppur - View & Read

• 1)

A parallel plate capacitor stores a charge Q at a voltage V. Suppose the area of the parallel plate capacitor and the distance between the plates are each doubled then which is the quantity that will change?

• 2)

Two short bar magnets have magnetic moments 1.20 Am2 and 1.00 Am2 respectively. They are kept on a horizontal table parallel to each other with their north poles pointing towards the south. They have a common magnetic equator and are separated by a distance of 20.0 cm. The value of the resultant horizontal magnetic induction at the mid-point O of the line joining their centers is (Horizontal components of Earth’s magnetic induction is 3.6 x 10-5 Wb m-2 )

• 3)

An inductor 20 mH, a capacitor 50 μF and a resistor 40 Ω are connected in series across a source of emf v = 10 sin 340 t. The power loss in AC circuit is

• 4)

Which of the following is an electromagnetic wave?

• 5)

A ray of light strikes a glass plate at an angle 60o. If the reflected and refracted rays are perpendicular to each other, the refractive index of the glass is,

#### 12th Standard Physics English Medium Free Online Test Book Back one Mark questions - Part Two - by Sarojini - Tiruppur - View & Read

• 1)

Three capacitors are connected in triangle as shown in the figure. The equivalent capacitance between the points A and C is

• 2)

A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of

• 3)

A flat dielectric disc of radius R carries an excess charge on its surface. The surface charge density is σ. The disc rotates about an axis perpendicular to its plane passing through the center with angular velocity ω. Find the magnitude of the torque on the disc if it is placed in a uniform magnetic field whose strength is B which is directed perpendicular to the axis of rotation

• 4)

In an oscillating LC circuit, the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electric and magnetic fields is

• 5)

Which of the following is NOT true for electromagnetic waves?

#### 12th Standard Physics English Medium Free Online Test Creative One Mark questions with Answer Key - Part Five - by Sarojini - Tiruppur - View & Read

• 1)

What physical quantities may X and Y represent? [Y represents the first mentioned quantity].

• 2)

In RLC series AC circuit at resonance:

• 3)

Which of the following forms a virtual and erect image for all position of the object.

• 4)

Sodium and copper have work functions of 2.3eV and 4.5eV respectively, then the ratio of the wavelengths is nearest to

• 5)

The de Broglie wavelength of electron accelerated with a potential V is ________

#### 12th Standard Physics English Medium Free Online Test Creative 1 Mark questions - Part Five - by Sarojini - Tiruppur - View & Read

• 1)

The unit for electric susceptibility is

• 2)

In an electrical arrangement as shown the equivalent resistance between X and Y will be

• 3)

Parts of the energy is used in an electric motor and the remaining part of the energy is dissipated in form of

• 4)

The magnitude of the induced emf in a conductor depends on the

• 5)

Speed of electromagnetic waves through vacuum is equal to

#### 12th Standard Physics English Medium Free Online Test Creative One Mark questions with Answer Key - Part Four - by Sarojini - Tiruppur - View & Read

• 1)

The magnitude of torque on dipole is maximum if

• 2)

The expression for water equivalent is

• 3)

For an ideal transformer __________

• 4)

Accelerated charges would produce

• 5)

_________ spectra are used for making dyes

#### 12th Standard Physics English Medium Free Online Test Creative 1 Mark questions - Part Four - by Sarojini - Tiruppur - View & Read

• 1)

In a hydrogen atom the electron revolves around the proton in an orbit of 0.53 $\mathring { A }$. The potential produced by the electron on the nuleus is

• 2)

If the specific resistance of a potentiometer wire is 10-7 Om and current flowing through it . is 0.1 amp, cross - sectional area of wire is 10-6 m2, then potential gradient will be

• 3)

The reciprocal of conductivity is________

• 4)

Direction of magnetic force on a positive charge moving in a magnetic field is given by

• 5)

Electric filament lamp gives rise to

#### 12th Standard Physics English Medium Free Online Test Creative One Mark questions with Answer Key - Part Three - by Sarojini - Tiruppur - View & Read

• 1)

Electric field intensity and electric potential are related by_________.

• 2)

When a current of 5 A flows through a conductor of resistance 3 $\Omega$ the loss of power due to joule heating effect is_________

• 3)

Which one of the following represents corrent magnetic field lines?

• 4)

If a secondary coil has 40 turns, and a primary coil with 20 turns is charged with 50V of potential difference, then potential difference in secondary would be

• 5)

Electromagnetic waves are discovered by

#### 12th Standard Physics English Medium Free Online Test Creative 1 Mark questions - Part Three - by Sarojini - Tiruppur - View & Read

• 1)

Eight mercury droplets having a radius of 1 mm and charge of 0.066 pC each merge to form one droplet. Its potential is

• 2)

The potential due to a single point charge falls as

• 3)

The emf of a battery is 3 volts and internal resistance 0.125 $\Omega$ . The difference of potential
at the terminal of battery when connected across an external resistance of 1 $\Omega$ is

• 4)

If a current I is flowing in a straight wire parallel to X-axis and magnetic field is in y-axis then the wire experiences

• 5)

The Q factor of an a.c. circuit containing a resistance R, inductance L and capacitor C is

#### 12th Standard Physics English Medium Free Online Test Creative One Mark questions with Answer Key - Part Two - by Sarojini - Tiruppur - View & Read

• 1)

The concept of 'Field' was introduced by

• 2)

A condenser is charged to a potential of 200V and has a charge of 0.1C. The energy stored in it is

• 3)

If the specific resistance of a potentiometer wire is 10-7 Om and current flowing through it . is 0.1 amp, cross - sectional area of wire is 10-6 m2, then potential gradient will be

• 4)

Which of the following is an identical.

• 5)

The resistance of the wire varies inversely as

#### 12th Standard Physics English Medium Free Online Test Creative 1 Mark questions - Part Two - by Sarojini - Tiruppur - View & Read

• 1)

An uncharged metal sphere is placed between two equal and oppositely charged metal plates. The nature of lines of force will be

• 2)

An unknown resistance is connected in parallel with a 15$\Omega$ resistance and a 12V battery. What is the value of the unknown resistance if the current in the circuit is 2A?

• 3)

Consider the motion of a charged particle in a uniform magnetic field directed into the paper. If velocity v of the particle is in the plane of the paper, the charged particle will describe a

• 4)

In the following figure the key is dosed. Which statement is correct?

• 5)

If the velocity of light in a medium is 2.25 x 108 ms-1 then the refractive index of the medium will be

#### 12th Standard Physics English Medium Free Online Test Volume 2 One Mark questions 2020 - by Sarojini - Tiruppur - View & Read

• 1)

When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index,

• 2)

When light is incident on a soap film of thickness 5×10–5 cm, the wavelength of light reflected maximum in the visible region is 5320 Å. Refractive index of the film will be,

• 3)

Two plane mirrors are at 45° to each other. If an object is placed between them than the number of images will be

• 4)

A ray of light is incidenting normally on a .plane mirror. The angle of reflection will be

• 5)

A point object 0 is placed between two plane mirrors as shown is figure The distance by mirror M2 from it are

#### 12th Standard Physics English Medium Free Online Test Volume 1 One Mark questions with Answer Key 2020 - by Sarojini - Tiruppur - View & Read

• 1)

The total electric fl ux for the following closed surface which is kept inside water

• 2)

A thin conducting spherical shell of radius R has a charge Q which is uniformly distributed on its surface. The correct plot for electrostatic potential due to this spherical shell is

• 3)

The relative permittivity of water is _______.

• 4)

What will happen if two conducting spheres are separately charged and then brought in contact?

• 5)

A non-conducting material which has no free electrons is called

#### 12th Standard Physics English Medium Free Online Test Volume 2 One Mark questions with Answer Key 2020 - by Sarojini - Tiruppur - View & Read

• 1)

A ray of light travelling in a transparent medium of refractive index n falls, on a surface separating the medium from air at an angle of incidents of 45o. The ray can undergo total internal reflection for the following n,

• 2)

One of the of Young’s double slits is covered with a glass plate as shown in figure. The position of central maximum will,

• 3)

A plane mirror produces a magnification of

• 4)

A plane mirror is placed at the bottom of the tank containing a liquid of refractive index J.1.P is a small object at a height h above the mirror, an observer O-vertically above P outside the liquid. See p and its image in the mirror. The apparent distance between these two will be

• 5)

The focal length of a convex mirror is 20 cm, its radius of the curvature will be

#### 12th Standard Physics English Medium Free Online Test Volume 1 One Mark questions 2020 - by Sarojini - Tiruppur - View & Read

• 1)

The total electric fl ux for the following closed surface which is kept inside water

• 2)

The relative permittivity of water is _______.

• 3)

An isolated metal sphere of radius 'r' is given a charge' q'. The potential energy of the sphere is

• 4)

The direction of electric field at a point the equatorial line due to an electric dipole is

• 5)

When three capacitors are joined in series, the total capacitance is

### TN Stateboard Education Study Materials

#### 12th Standard Physics English Medium Reduced Syllabus 2020 - 2021 - by QB Admin Jan 23, 2021 Jan 23, 2021

Reduced Syllabus and Chapters for 12th Standard Physics English Medium

The His

#### 12th Stateboard Physics 2019 - 2020 Academic Monthly Syllabus - by Sarojini - Tiruppur Aug 02, 2019 Aug 02, 2019

Physics 2019 - 2020 Academic Monthly Syllabus

### TN Stateboard Updated Class 12th Physics Syllabus

#### Electrostatics

Introduction - Coulomb's Law - Electric Field and Electric Field Lines - Electric dipole and Its Properties - Electrostatic Potential and Potential Energy - Gauss Law and Its Applications - Electrostatics of Conductors and Dielectrics - Capacitors and Capacitance - Distribution of Charges In A Conductor and Action At Points

#### Current Electricity

Introduction - Electric Current - Ohm’s Law - Energy and Power In Electrical Circuits - Electric Cells and Batteries - Kirchhoff ’s Law - Heating Effect of Electric Current - Thermoelectric Current

#### Magnetism and magnetic effects of electric current

Introduction of Magnetism - Coulomb's Inverse Square Law of Magnetism - Torque Acting On a Bar Magnet In Uniform Magnetic Field - Magnetic Properties - Classification of Magnetic Materials - Hysteresis - Magnetic Effects of Current - Biot - Savart Law - Ampere’s Circuital Law - Lorentz Force - Torque On a Current Loop

#### Electromagnetic Induction And Alternating Current

Introduction - Electromagnetic Induction - Eddy currents - Self-Induction - Methods of Producing Induced EMF - AC Generator - Transformer - Alternating Current - Power
In AC Circuits - Oscillations In LC Circuits

#### Electromagnetic waves

Introduction - Electromagnetic Waves - Types of Spectrum-Emission and Absorption Spectrum-Fraunhofer Lines

#### TN StateboardStudy Material - Sample Question Papers with Solutions for Class 12 Session 2020 - 2021

Latest Sample Question Papers & Study Material for class 12 session 2020 - 2021 for Subjects Maths, Chemistry, Biology, Computer Science, Business Maths, Economics, Commerce, Accountancy, History, Computer Applications, Computer Technology, English, உயிரியல், கணினி பயன்பாடுகள், கணினி அறிவியல், வணிகக் கணிதம், வணிகவியல், பொருளியல், கணிதவியல், வேதியியல், இயற்பியல், கணினி தொழில்நுட்பம், வரலாறு, கணக்குப்பதிவியல், தமிழ் in PDF form to free download [ available question papers ] for practice. Download QB365 Free Mobile app & get practice question papers.

More than 1000+ TN Stateboard Syllabus Sample Question Papers & Study Material are based on actual Board question papers which help students to get an idea about the type of questions that will be asked in Class 12 Final Board Public examinations. All the Sample Papers are adhere to TN Stateboard guidelines and its marking scheme , Question Papers & Study Material are prepared and posted by our faculty experts , teachers , tuition teachers from various schools in Tamilnadu.

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