#### 11th Standard Physics Heat and Thermodynamics English Medium Free Online Test One Mark Questions 2020 - 2021

11th Standard

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Physics

Time : 00:20:00 Hrs
Total Marks : 20

20 x 1 = 20
1. In hot summer after a bath, the body’s

(a)

internal energy decreases

(b)

internal energy increases

(c)

heat decreases

(d)

no change in internal energy and heat

2. An ideal gas is taken from (Pi,Vi) to (P$\rho$ ,Vf) in three different ways. Identify the process in which the work done on the gas the most.

(a)

Process A

(b)

Process B

(c)

Process C

(d)

Equal work is done in Process A,B &C

3. A distant star emits radiation with maximum intensity at 350 nm. The temperature of the star is

(a)

8280 K

(b)

5000K

(c)

7260 K

(d)

9044 K

4. In an isochoric process, we have

(a)

W = 0

(b)

Q = 0

(c)

ΔU = 0

(d)

ΔT = 0

5. When an ideal diatomic gas is heated at constant pressure, the fraction of the heat energy applied which increases the internal energy of gas is

(a)

$\frac { 2 }{ 5 }$

(b)

$\frac { 3 }{ 5 }$

(c)

$\frac { 3 }{ 7 }$

(d)

$\frac { 5 }{ 7 }$

6. Two thermally insulated vessels 1 & 2 are filled with air at temp (T, T2), volume (V1,'V2 & pressure (P1 P2)' If the valve going to the 2 vessels is opened, the temperature on the inside of the vessel at equilibrium will be

(a)

T1 + T2

(b)

$\frac { { T }_{ 1 }+{ T }_{ 2 } }{ 2 }$

(c)

$\frac { { T }_{ 1 }{ T }_{ 2 }\left( { P }_{ 1 }{ V }_{ 1 }+{ P }_{ 2 }{ V }_{ 2 } \right) }{ { P }_{ 1 }{ V }_{ 1 }{ T }_{ 2 }+{ P }_{ 2 }{ V }_{ 2 }{ T }_{ 1 } }$

(d)

$\frac { { T }_{ 1 }{ T }_{ 2 }\left( { P }_{ 1 }{ V }_{ 1 }+{ P }_{ 2 }{ V }_{ 2 } \right) }{ { P }_{ 1 }{ V }_{ 1 }{ T }_{ 1 }+{ P }_{ 2 }{ V }_{ 2 }{ T }_{ 2 } }$

7. Volume - temperature graph at atmospheric pressure for a mono atomic gas (V in m3, Tin °C) is

(a)

(b)

(c)

(d)

8. The mean kinetic energy of one mole of gas per degree of freedom (on basis of kinetic theory of gases) is

(a)

$\frac { 1 }{ 2 }$kT

(b)

$\frac { 3 }{ 2 }$ kT

(c)

$\frac { 3 }{ 2 }$ RT

(d)

$\frac { 1 }{ 2 }$ RT

9. Which one is correct?

(a)

In an isobaric, $\triangle$p = 0

(b)

In an isochoric process, $\triangle$ W = 0

(c)

In an isothermal, $\triangle$T = 0

(d)

In an isothermal process, $\triangle$Q = 0

10. Calculate the work done if temperature is changed from O°Cto 200°C at one atm. [R = 2 cal K-1]

(a)

100 cal

(b)

200 cal

(c)

100 cal

(d)

800 cal

11. In an isothermal process

(a)

there is no change in internal energy

(b)

there is no change in temperature

(c)

there is no change in enthalpy

(d)

all the above

12. During which of the following process does heat rejection takes place in carnot cycle?

(a)

isothermal expansion

(b)

(c)

isothermal compression

(d)

13. The sum of internal energy (U) and the product of pressure and volume (P.V.) is

(a)

enthalpy

(b)

work done

(c)

entropy

(d)

none

14. A solid metal ball has a spherical cavity. If the ball is heated, the volume of the cavity will

(a)

increase

(b)

decrease

(c)

remain unaffected

(d)

remain unaffected but the shape of the cavity will change

15. The length of a metal rod at 0°C is 0.5m. When it is heated, its length increases by 2.7 mm. The final temperature of the rod is (coefficient of linear expansion of the metal = 90 x 10-6/°C) _______.

(a)

20°C

(b)

30°C

(c)

40°C

(d)

60°C

16. When water is heated from 0oC to 0oC, its volume ________.

(a)

decreases

(b)

increases

(c)

first increase and then decrease

(d)

first decreases and then increases

17. 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

18. Which of the following will make the volume of an ideal gas four times?

(a)

double the absolute temperature and double the pressure

(b)

Halve the absolute temperature and double the pressure.

(c)

Quarter the absolute temperature at constant pressure.

(d)

Quarter the pressure at constant temperature.

19. An air bubble doubles in radius on rising from the bottom of a lake to its surface. If the atmospheric pressure is equal to that of a column of water of height H, the depth of lake is

(a)

H

(b)

2H

(c)

7H

(d)

8H

20. A temperature difference of 25°C is equivalent to a temperature difference of

(a)

25°F

(b)

45°F

(c)

67°F

(d)

77°F