11. Which of the following characteristics are required by the medium for transfer of energy to take place?

1. Elastic property
2. Property of inertia
3. Large frictional resistance

(a) 1 and 2 only
(b) 1 and 3 only
(c) 2 and 3 only
(d) 1, 2 and 3

Answer: (a)

12. A substance undergoes a change in pressure or volume but no heat is allowed to enter or leave. Such a change is known as:
(a) Isothermal change
(b) Reversible change
(c) Irreversible change
(d) Adiabatic change

Answer: (d)

13. Which of the following are non-polar molecules?
1. Oxygen (𝑂2)
2. Nitrogen(𝑁2)
3. Hydrogen (𝐻2)

(a) 1 and 2 only
(b) 1 and 3 only
(c) 2 and 3 only
(d) 1, 2 and 3

Answer: (d)

14.
(a) 1.10
(b) 1.35
(c) 1.85
(d) 1.50

Answer: (d)

15. What is the highest order spectrum which may be seen with monochromatic light of wavelength 600 nm by means of diffraction grating with 5000 lines/cm?
(a) 1
(b) 2
(c) 3
(d) 4

Answer: (c)

16. 

Answer: (c)

17. Wavelength 𝜆 associated with a moving particle depends on its mass 𝑚 , velocity of motion 𝑣 and Plank’s constant ℎ. then the wavelength is proportional to:

Answer: (c)

18. A reversible engine takes in a mixture of fuel and air at 27°𝐶 and the highest temperature after combustion is 427°𝐶. What is the Carnot’s efficiency of the engine working between these two temperature limits?
(a) 52.7 %
(b) 57.1 %
(c) 47.1 %
(d) 42.7 %

Answer: (b)

19. 
(a) 1.5 Ω
(b) 4.5 Ω
(c) 3.5 Ω
(d) 2.5 Ω

Answer: (d)

20. The luminous efficiency of a lamp is 5 lumen/watt and its power is 88 watt. What is the illuminance on a surface placed at a distance of 10 𝑚 , when the light is falling normally?
(a) 0.35 lux
(b) 0.6 lux
(c) 0.5 lux
(d) 0.45 lux

Answer: (a)