#### 11th Standard Physics English Medium Free Online Test 1 Mark Questions 2020 - Part Six

11th Standard

Reg.No. :
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Physics

Time : 00:25:00 Hrs
Total Marks : 25

25 x 1 = 25
1. The density of a material in CGS system of units is 4 g cm-3 . In a system of units in which unit of length is 10 em and unit of mass is 100 g, then the value of density of material will be

(a)

0.04

(b)

0.4

(c)

40

(d)

400

2. Which is deals with the study of materials of an intermediate length scale.

(a)

Macroscopic physics

(b)

Macroscopic physics

(c)

Microscopic physics

(d)

All the above

3. The Van der Waal equation for n moles of a real gas is $(P+\frac{a}{V^2})(V-b)=RT$ where P is the pressure. V is the volume. T is the absolute temperature. R is the molar gas constant and 'a' and 'b' are Van der Waal constants. The dimensions of 'a' are the same as those of

(a)

$\frac{P}{V}$

(b)

PV

(c)

PV2

(d)

P2V

4. Dimensional formula of self inductance is

(a)

[MLT-2A-2]

(b)

[ML2T-1A-2]

(c)

[ML2T-2A-2]

(d)

[ML-2T-2A-1]

5. If a particle executes uniform circular motion, choose the correct statement

(a)

The velocity and speed are constant

(b)

The acceleration and speed are constant.

(c)

The velocity and acceleration are constant.

(d)

The speed and magnitude of acceleration are constant.

6. $\vec A$and $\vec B$ are perpendicular if $\vec A$· $\vec B$ = :

(a)

1

(b)

0

(c)

$\infty$

(d)

$\frac {\vec A}{\vec B}$

7. The magnitude of a vector cannot be

(a)

positive

(b)

negative

(c)

zero

(d)

90

8. A particle of mass m sliding on the smooth double inclined plane (shown in figure) will experience

(a)

greater acceleration along the path AB

(b)

greater acceleration along the path AC

(c)

same acceleration in both the paths

(d)

no acceleration in both the paths

9. A body of mass 5 kg is suspended by a spring balance on an inclined plane as shown in figure. The spring balance measure.

(a)

50 N

(b)

25 N

(c)

500 N

(d)

10 N

10. Which of the following is the dimension of coefficient of friction?

(a)

[MLT-2]

(b)

[M0L0T0]

(c)

[M2LT-2]

(d)

[M2LT]

11. The condition for skidding is

(a)

tanθ=μ

(b)

tanθ < μ

(c)

tanθ > μ

(d)

tanθ = 0

12. If a body is raised from the surface of the earth upto height R, what is the change in potential energy?

(a)

mgR

(b)

$\frac{3}{2}mgR$

(c)

$\frac{mgR}{2}$

(d)

$\frac{mgR}{4}$

13. Consider a system of two identical particles. One is at rest and the other has an acceleration $\overrightarrow { a }$ .The centre of mass has an acceleration

(a)

1/2$\overrightarrow { a }$

(b)

$\overrightarrow { a }$

(c)

2$\overrightarrow { a }$

(d)

Zero

14. Two discs are rotating about their axes, normal to the discs and passing through the centres of the discs. Disc D1 has D2 kg mass and 0.2 m radius and initial angular velocity of 50 cad s-1, Disc D2, has 4 kg mass, 0.1 m radius and initial angular velocity of 200 rad s-1 The two discs are brought in contact face to face, with their axes of rotation coincident. The final angular velocity (in rad s-1) of the system is

(a)

60

(b)

100

(c)

120

(d)

40

15. If the masses of the Earth and Sun suddenly double, the gravitational force between them will

(a)

remain the same

(b)

increase 2 times

(c)

increase 4 times

(d)

decrease 2 times

16. A body of mass 500g is town upwards with a velocity 20ms-1 and reaches back to the surface of a planet after 20s. Then the weight of the body on that planet is

(a)

2 N

(b)

4 N

(c)

5 N

(d)

1 N

17. Water rises in a capillary tube to a certain height such that the upward force due to the surface tension is balanced by 62.84 x 10-5N force due to the weight of the liquid column. If the surface tension of water is 70 x 10-3Nm the radius of the capillary tube is

(a)

1.43 x 10-3m

(b)

2.83x 10-3 m

(c)

1.43x 10-2 m

(d)

2.83 x 10-3 m

18. The surface tension phenomenon is the result of the tendency of a system to ________.

(a)

conserve energy

(b)

conserve volume

(c)

keep potential energy minimum

(d)

keep surface area minimum

19. An iron tyre is to be fitted on a wooden wheel O.lm in diameter. The diameter of the tyre is 6 mm smaller than that of the wheel. The tyre should be heated by a temperature of (coefficient of volume expansion of iron is 3.6 x 10-5/°C) ________

(a)

167°C

(b)

334°C

(c)

500oC

(d)

1000oC

20. We consider a thermodynamic system. If $\Delta$U represent the increase in its energy and W the work done by the system, which of the following statements is true?

(a)

$\Delta$U = - W in an isothermal process

(b)

$\Delta$U = - W in an adiabatic process

(c)

$\Delta$U = - W in an isothermal process

(d)

$\Delta$U =W in an adiabatic process

21. An ideal gas heat engine operators in a carnot's cycle between 227°C and 127°C. It absorbs 6 x 104J at high temperature. The amount of heat converted into work is ________.

(a)

2.4 x 104J

(b)

4.8 x 104J

(c)

1.2 x 104J

(d)

6 x 104J

22. A real gas behaves as an ideal gas at _________.

(a)

low pressure and high temperature

(b)

high pressure and low temperature

(c)

low pressure and low temperature

(d)

high pressure and high temperature.

23. What is time period of a pendulum hanged in a satellite? (T is time period on earth)

(a)

zero

(b)

T

(c)

infinite

(d)

$\frac { T }{ \sqrt { 6 } }$

24. Sound travels fastest in _________.

(a)

Steel

(b)

air

(c)

water

(d)

vacuum

25. The velocity of sound in are is not affected by change in the ________.

(a)

atmospheric pressure

(b)

moisture content of air

(c)

temperature of air

(d)

composition of air