NEET Physics - New - Thermodynamics

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Question - 1

The volume (V) of a monatomic gas varies with its temperature (T), as shown in the graph. The ratio of work done by the gas, to the heat absorbed by it, when it undergoes a change from state A to state B, is

  • A 1/3
  • B 2/3
  • C 2/5
  • D 2/7

Question - 2

The efficiency of an ideal heat engine working between the freezing point and boiling point of water, is:

  • A 6.25%
  • B 20%
  • C 26.8%
  • D 12.5%

Question - 3

Thermodynamic processes are indicated in the following diagram:

Match the following:

Column-1 Column-2
P. Process I a. Adiabatic
Q. Process II b. Isobaric
R. Process III c. Isochoric
S. Process IV d. Isothermal
  • A P - c, Q - a, R - d, S - b
  • B P-c, Q - d, R- b, S-a
  • C P-d, Q-b, R-a, S-c
  • D P-a, Q-c, R-d, S-b

Question - 4

A refrigerator works between 4°C and 30°C. It is required to remove 600 calories of heat every second in order to keep the temperature of the refrigerated space constant. The power required is [Take 1 cal = 4.2 joules)

  • A 236.5 W
  • B 2365 W
  • C 2.365 W
  • D 23.65 W

Question - 5

A piece of ice falls from a height h so that it melts completely. Only one-quarter of the heat produced is absorbed by the ice and all energy of ice gets converted into heat during its fall. The value of h is [Latent heat of ice is 3.4 x 105 J/kg and g = 10 N/kg]

  • A 136 km
  • B 68 km
  • C 4 km
  • D 544 km

Question - 6

An ideal gas is compressed to half its initial volume by means of several processes. Which of the process results in the maximum work done on the gas?

  • A Isothermal
  • B Adiabatic
  • C Isobaric
  • D Isochoric

Question - 7

Figure below shows two paths that may be taken by a gas to go from a state A to a state C. In process AB, 400 J of heat is added to the system and in process BC, 100 J of heat is added to the system. The heat absorbed by the system in the process AC will be:

  • A 380 J
  • B 500 J
  • C 460 J
  • D 300 J

Question - 8

One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown in figure. The change in the internal energy of the gas during the transition is:

  • A 20 kJ
  • B -20 kJ
  • C 20 J
  • D -12 kJ

Question - 9

Amonoatomic gas at a pressure P, having a volume V expands isothermally to a volume 2 V and then adiabatically to a volume 16 V. The final pressure of the gas is \(\left(\text { take } \gamma=\frac{5}{3}\right)\)

  • A 64 P
  • B 32 P
  • C \(\frac{p}{64}\)
  • D 16 P

Question - 10

Athermodynamic system undergoes cyclic process ABCDA as shown in figure. The work done by the system in the cycle is :

  • A P0V0
  • B 2P0V0
  • C P0V0/2
  • D Zero