NEET JEE Physics QUIZ - Thermodynamics AUGUST 11

Physics MCQ Test

Thermodynamics & Heat — 10 Questions

10 MCQs

Instructions:
Select one answer for each question. Click Submit Test to see your score. Correct answers will be revealed only after submission.

1. If an ideal flask containing hot coffee is shaken, the temperature of the coffee will:

(1) Decrease (2) Increase (3) Remain same (4) Decrease if temperature is below 4°C and increase if it is 4°C or more

Correct Answer: (3) Remain same

2. Water is used to cool the radiators of engines in cars because:

(1) It has a low boiling point (2) It has a high specific heat (3) It has a low density (4) It has an easy density

Correct Answer: (2) It has a high specific heat

3. Work done in a thermodynamic process depends on:

(1) Initial state only (2) Final state only (3) Initial and final states only (4) Initial state, final state and path

Correct Answer: (4) Initial state, final state and path

4. A diatomic ideal gas is used as the working substance in a Carnot engine. During adiabatic expansion, its volume increases from V to 32V. What is the efficiency of the engine?

(1) 0.25 (2) 0.50 (3) 0.75 (4) 0.99

Correct Answer: (3) 0.75

5. Even a Carnot engine cannot give 100% efficiency because we cannot:

(1) Prevent radiation (2) Find ideal sources (3) Reach absolute zero temperature (4) Eliminate friction

Correct Answer: (3) Reach absolute zero temperature

6. “Heat cannot be itself flow from a body at lower temperature to a body at higher temperature” is a statement or consequence of:

(1) Conservation of momentum (2) Conservation of mass (3) First law of thermodynamics (4) Second law of thermodynamics

Correct Answer: (4) Second law of thermodynamics

7. For a given quantity of an ideal gas at pressure P and absolute temperature T, the isothermal bulk modulus of the gas is:

(1) (2/3)P (2) P (3) (3/2)P (4) 2P

Correct Answer: (2) P

8. A gas mixture consists of 2 moles of oxygen and 4 moles of argon at temperature T. Neglecting all vibrational modes, the total internal energy of the system is:

(1) 4RT (2) 15RT (3) 9RT (4) 11RT

Correct Answer: (4) 11RT

9. For equal expansion of a gas, the work done in increasing order is:

(1) Adiabatic > Isothermal > Isobaric (2) Isobaric > Adiabatic > Isothermal (3) Adiabatic > Isobaric > Isothermal (4) None of the above

Correct Answer: (4) None of the above — the increasing order is Adiabatic < Isothermal < Isobaric

10. A system does 50 J of work under adiabatic conditions. In this process:

(1) Temperature of the system will increase (2) Temperature of the system will remain constant (3) Internal energy of the system will increase (4) Internal energy of the system will decrease

Correct Answer: (4) Internal energy of the system will decrease