The perfect gas goes from a state A to another state B by absorbing $8 \times {10^5}$J of heat and doing $6.5 \times {10^5}{\rm{J}}$of external work. It is now transferred between the same two states in another process in which it absorbs ${10^5}J$ of heat in the second process. Then

Work done on the gas is $0.5 \times {10^5}{\rm{J}}$

Work done on the gas is ${10^5}J$

One mole of an ideal monoatomic gas is heated in a constant pressure of one atmosphere from $0^\circ \,C$ to $100^\circ \,C$. Then the change in the internal energy is

$12.48 \times {10^2}{\rm{ joules}}$

$8.32 \times {10^2}{\rm{ joules}}$

Back to THERMODYNAMICS

Your Progress

0 / 183 Answered

Correct

Incorrect

Accuracy

NEET • PHYSICS • THERMODYNAMICS

Thermodynamics practice · Mixed difficulty

Try a question, then open “View answer” to check it. Sign in to submit answers and save progress.

Practice format and chapter quiz

The practice player uses single-correct-answer MCQs. Chapter quizzes help you review a topic; they are not full-length NEET mock papers.

Take a chapter quiz →

Showing 1-30 of 183 questions

1 Medium

1 of 183

Analyzing +4 | -1

The work done during expansion of a gas is independent of pressure if the expansion takes place

View answer and explanation

Correct option: D

In none of the above cases

The correct answer is D because the work done during the expansion of a gas depends on the pressure, regardless of whether the process is isothermal or adiabatic.

2 Easy

2 of 183

Understanding +4 | -1

When heat is added to a system, which of the following is not possible?

View answer and explanation

Correct option: C

Neither internal energy increases nor work is done by the system

Option C (Neither internal energy increases nor work is done by the system) is correct because if heat is added to a system, at least one of the internal energy or work done by the system must increase according to the first law of thermodynamics.

3 Medium

3 of 183

Remembering +4 | -1

The

p-T

relation for an adiabatic expansion is

View answer and explanation

Correct option: D

p^{1-\gamma} T^\gamma=

constant

Option D is correct because the correct p-T relation for an adiabatic process is given by

p^{1-\gamma}T^{\gamma} = constant

4 Medium

4 of 183

Application +4 | -1

A Carnot engine has efficiency

\frac{1}{4}

. Efficiency becomes

\frac{1}{3}

when temperature of sink is decreased by 50 K (keeping source fixed). What is the original temperature of the sink?

View answer and explanation

Correct option: D

450 K

Option D (450 K) is correct because it is the original temperature of the sink calculated from the Carnot engine efficiency equations.

5 Easy

5 of 183

Application +4 | -1

If sink and source temperature of a refrigerator are

4^{\circ} \mathrm{C}

and

15^{\circ} \mathrm{C}

respectively. Then efficiency of refrigerator is

View answer and explanation

Correct option: B

0.0382

Option A (0.0382) is correct because the efficiency of a refrigerator is calculated using the formula

\eta = 1 - \frac{{T_2}}{{T_1}}

, where

T_1

and

T_2

are the source and sink temperatures in Kelvin.

6 Medium

6 of 183

Understanding +4 | -1

The

SI

unit of mechanical equivalent of heat is

View answer and explanation

Correct option: B

Joule/Calorie

Option B is correct because the mechanical equivalent of heat (J) relates the amount of work (in Joules) to the amount of heat (in Calories), so its unit is Joule/Calorie.

7 Medium

7 of 183

Remembering +4 | -1

Which of the following is/are thermodynamic coordinate?

View answer and explanation

Correct option: D

All of the above

Option D (All of the above) is correct because volume, pressure, and temperature are all state variables that define the thermodynamic state of a system.

8 Easy

8 of 183

Understanding +4 | -1

Temperature is a measure of coldness or hotness of an object. This definition is based on

View answer and explanation

Correct option: A

Zeroth law of thermodynamics

Option A (Zeroth law of thermodynamics) is correct because the zeroth law defines thermal equilibrium and provides the basis for temperature measurement.

9 Medium

9 of 183

Application +4 | -1

In the certain process, 400 cal of heat are supplied to a system and at the same time 105 J of mechanical work was done on the system. The increase in its internal energy is

View answer and explanation

Correct option: D

425 cal

Option D (425 cal) is correct because it is the increase in internal energy calculated using the first law of thermodynamics:

\Delta U = Q - W

, where W is negative when work is done on the system.

10 Medium

10 of 183

Understanding +4 | -1

A thermally insulated container is divided into two parts by a screen. In one part the pressure and temperature are

P

and

T

for an ideal gas filled. In the second part it is vacuum. If now a small hole is created in the screen, then the temperature of the gas will

View answer and explanation

Correct option: C

Remain same

Option C (Remain same) is correct because the process is a free expansion into a vacuum, which is an irreversible adiabatic process with no work done and no heat exchange, resulting in no change in temperature for an ideal gas.

11 Hard

11 of 183

Understanding +4 | -1

In an adiabatic process, which of the following
statements is true?

View answer and explanation

Correct option: C

The molar heat capacity is zero

Option C (The molar heat capacity is zero) is correct because in an adiabatic process, there is no heat transfer (Q=0), and molar heat capacity is defined as C = Q/nΔT, so C=0.

12 Easy

12 of 183

Understanding +4 | -1

The internal energy of a system remains constant
when it undergoes

(A) a cycle process

(B) an isothermal process

(C) an adiabatic process

(D) any process in which the heat given out by the
system is equal to the work done on the system

Choose the correct statement

View answer and explanation

Correct option: D

A, B, D

The correct answer is D (A, B, D) because internal energy remains constant in a cyclic process, an isothermal process, and any process where heat given out equals work done on the system.

13 Medium

13 of 183

Analyzing +4 | -1

Assertion: PV value of gas can increase on increasing the pressure.
Reason: Pressure always increases on compression.

View answer and explanation

Correct option: C

If assertion is True but the Reason is False

Option C (If assertion is True but the Reason is False) is correct because PV can increase with pressure, but pressure doesn't always increase on compression.

14 Medium

14 of 183

Understanding +4 | -1

A gas undergoes an adiabatic change. Its specific heat in the process is

View answer and explanation

Correct option: A

Zero

Option A (Zero) is correct because in an adiabatic process, there is no heat transfer (Q=0), so the specific heat (c = Q/mΔT) is zero.

15 Medium

15 of 183

Application +4 | -1

The perfect gas goes from a state A to another state B by absorbing

8 \times {10^5}

J of heat and doing

6.5 \times {10^5}\mathrm{J}

of external work. It is now transferred between the same two states in another process in which it absorbs

{10^5}J

of heat in the second process. Then

View answer and explanation

Correct option: A

Work done on the gas is

0.5 \times {10^5}\mathrm{J}

Work done on the gas is

0.5 \times {10^5}\mathrm{J}

because the change in internal energy is path-independent, and the difference in heat absorbed corresponds to the difference in work done.

Explore Other Chapters in PHYSICS

View All →

UNITS & MEASUREMENTS 392 MCQs WORK-ENERGY-POWER 355 MCQs MECHANICAL PROPERTIES OF FLUIDS 317 MCQs MOTION IN PLANE 307 MCQs MAGNETIC EFFECT OF CURRENT 282 MCQs THERMAL PROPERTIES OF MATTER 269 MCQs

16 Easy

16 of 183

Application +4 | -1

Find the amount of workdone to increase the temperature of one mole of an ideal gas by

30^{\circ} \mathrm{C}

if it is expanding under the condition

V \propto T^{2 / 3},(R=1.99 \mathrm{cal} / \mathrm{mol}-\mathrm{K})

View answer and explanation

Correct option: A

167

Option A (167) is correct because the work done is calculated using the given relation between volume and temperature and the ideal gas constant.

17 Medium

17 of 183

Understanding +4 | -1

The internal energy of the gas increases in

View answer and explanation

Correct option: B

Adiabatic compression

Option B (Adiabatic compression) is correct because in adiabatic compression, work is done on the gas, increasing its internal energy since no heat is exchanged.

18 Medium

18 of 183

Remembering +4 | -1

The adiabatic Bulk modulus of a perfect gas at pressure is given by

View answer and explanation

Correct option: D

\gamma P

Option D (

\gamma P

) is correct because the adiabatic bulk modulus of a perfect gas is given by the formula

\gamma P

, where

\gamma

is the adiabatic index and P is the pressure.

19 Medium

19 of 183

Understanding +4 | -1

Which of the following is unique function of initial and final states?

View answer and explanation

Correct option: C

Option C (dU) is correct because dU represents the change in internal energy, which is a state function and depends only on the initial and final states.

20 Medium

20 of 183

Remembering +4 | -1

The thermodynamic process, in which internal energy of the system remains constant is

View answer and explanation

Correct option: C

Isothermal

Option C (Isothermal) is correct because an isothermal process is defined as a process occurring at constant temperature, implying constant internal energy for an ideal gas.

21 Hard

21 of 183

Application +4 | -1

One mole of an ideal diatomic gas undergoes a thermodynamic process, in which its molar heat capacity varies directly proportional to temperature as

{C}=\alpha{T}

, where

\alpha

is a positive constant. Work done by the gas when it is heated from initial temperature

T_0

to a final temperature

3 T_0

will be

View answer and explanation

Correct option: C

\left(4 \alpha {T}_0-5 {R}\right) {T}_0

Option C (

\left(4 \alpha {T}_0-5 {R}\right) {T}_0

) is correct because it represents the work done calculated by integrating the heat capacity over the temperature range and applying the first law of thermodynamics.

22 Hard

22 of 183

Application +4 | -1

One mole of an ideal monoatomic gas is heated in a constant pressure of one atmosphere from

0^\circ \,C

100^\circ \,C

. Then the change in the internal energy is

View answer and explanation

Correct option: C

12.48 \times {10^2}\mathrm{ joules}

The change in the internal energy is

12.48 \times {10^2}\mathrm{ joules}

because it is calculated using the formula

\Delta U = nC_v\Delta T

for a monoatomic gas.

23 Medium

23 of 183

Understanding +4 | -1

It is difficult to cook rice in an open vessel by boiling it a high altitudes because of

View answer and explanation

Correct option: C

Low boiling point and low pressure

Option C (Low boiling point and low pressure) is correct because at high altitudes, the atmospheric pressure is lower, which reduces the boiling point of water, making it difficult to cook rice.

24 Medium

24 of 183

Remembering +4 | -1

The Davison – Germer experiment is direct evidence of

View answer and explanation

Correct option: B

Wave nature of electron

Option B (Wave nature of electron) is correct because the Davisson-Germer experiment demonstrated the diffraction of electrons, confirming their wave-like properties.

25 Medium

25 of 183

Application +4 | -1

{C_V} = 4.96cal/mole K

,then increase in internal energy when temperature of 2 moles of this gas is increased from

340K

342K

View answer and explanation

Correct option: B

19.84cal

Option B (

19.84cal

) is correct because it is the increase in internal energy calculated using the formula

\Delta U = nC_V \Delta T

26 Medium

26 of 183

Understanding +4 | -1

When heat is given to a gas in an isobaric process, then

View answer and explanation

Correct option: C

Both 1 and 2

Option C (Both 1 and 2) is correct because in an isobaric process, heat added does both work and increases internal energy.

27 Medium

27 of 183

Understanding +4 | -1

dU+dW=0 is valid for

View answer and explanation

Correct option: D

Isochoric process

Option D (Isochoric process) is correct because in an isochoric process, the volume is constant, so no work is done (dW=0), and thus dU+dW=dU=0 if the process is also isothermal.

28 Medium

28 of 183

Remembering +4 | -1

Two systems in thermal equilibrium with a third system separately are in thermal equilibrium with each other.

View answer and explanation

Correct option: D

Zeroth law of thermodynamics

Option D (Zeroth law of thermodynamics) is correct because it describes the transitive property of thermal equilibrium.

29 Easy

29 of 183

Understanding +4 | -1

Assertion: Internal energy of an ideal gas does not depend upon volume of the gas.
Reason: Internal energy of ideal gas depends on temperature of gas.

View answer and explanation

Correct option: B

If both assertion and reason are true but reason is not correct explanation of the assertion

Option B (If both assertion and reason are true but reason is not correct explanation of the assertion) is correct because while both statements are true, the reason doesn't directly explain why the assertion is true. The assertion is true because ideal gases have no intermolecular forces.

30 Medium

30 of 183

Analyzing +4 | -1

n_1

and

n_2

are the moles of two ideal gases, whose thermodynamics constants, [ratio of

\left(\frac{C_p}{C_v}\right)

] are

\gamma_1

and

\gamma_2

respectively, are mixed.

\left(\frac{C_p}{C_v}\right)

for the mixture is-

View answer and explanation

Correct option: D

\frac{n_1 \gamma_1\left(\gamma_2-1\right)+n_2 \gamma_2\left(\gamma_1-1\right)}{n_1\left(\gamma_2-1\right)+n_2\left(\gamma_1-1\right)}

Option D is correct because it represents the correct formula for calculating the ratio of specific heats for a mixture of ideal gases based on their individual ratios and mole fractions.

Revision notes and key takeaways

Review THERMODYNAMICS in your textbook or class notes, then use this set to check your understanding.

Key Takeaways

✓ This set contains 183 single-correct-answer MCQs on THERMODYNAMICS.
✓ Try each question before opening its answer. Read the explanation where one is available.
✓ Sign in to save submitted answers. Revisit incorrect answers alongside your textbook or class notes.

Showing 1-30 of 183 questions

Continue Your Practice

📚 Switch Set (ALL)

Chapter Sets

ALL 183 MCQs EASY 40 MCQs HARD 17 MCQs MEDIUM 126 MCQs

0 /183

0✓ 0✗

0% Accuracy