NEET Physics - New - Thermodynamics

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