JEE Physics - MCQ Practice Questions

A thermodynamic system does 600 J of work while 2400 J of heat is supplied to it. What is the change in internal energy?

For a reversible isothermal process of an ideal gas, the entropy change of the universe is:

A gas undergoes a process where PV² = constant. If the gas expands from volume V to 2V, what is the ratio of final to initial pressure?

A system absorbs 8000 J of heat and its internal energy increases by 5000 J. According to the first law of thermodynamics, what work is done by the system?

For an ideal gas undergoing a polytropic process (PV^n = constant), the heat capacity is C = C_v + R/(1-n). For which value of n does the polytropic process become adiabatic?

A thermally insulated container holds 2 moles of oxygen gas at 300 K. A heating element supplies 5000 J of heat to the gas. What is the final temperature? (C_v for O₂ = 5R/2, R = 8.314 J/mol·K)

For a Carnot refrigerator operating between 250 K (cold reservoir) and 300 K (hot reservoir), the coefficient of performance (COP) is:

A substance has a latent heat of vaporization of 2260 kJ/kg at 373 K. The entropy change during vaporization of 1 kg of water is approximately:

When a system undergoes a process where both Q and W are positive, which statement is true?

A gas sample at 300 K has an entropy of 200 J/K. When heated at constant pressure to 600 K, its entropy becomes:

Which thermodynamic process results in maximum work extraction from an ideal gas expanding from the same initial to final states?

A heat engine operates between two reservoirs at temperatures 500 K and 300 K. What is the maximum theoretical efficiency of this engine?

Three moles of an ideal diatomic gas are heated at constant pressure from 300 K to 600 K. Calculate the heat absorbed by the gas. (R = 8.314 J/mol·K)

A gas expands isothermally from volume V₁ to 3V₁ at temperature T. If the initial pressure is P₁, what is the work done by the gas?

A system undergoes a cyclic process. The internal energy change over one complete cycle is ΔU. Which statement is correct?

Two identical blocks at different temperatures are brought into thermal contact in an isolated system. Block A at 400 K and Block B at 300 K both have mass 1 kg and specific heat 400 J/kg·K. What is the change in entropy of the universe?

An ideal gas undergoes an adiabatic process from state (P₁, V₁, T₁) to (P₂, V₂, T₂) with γ = 1.4. If volume increases by 50%, the temperature ratio T₂/T₁ is approximately:

A refrigerator operates with a COP (Coefficient of Performance) of 4 between temperatures 250 K and 350 K. What is the theoretical maximum COP possible?

A 2 kg mass of ice at 0°C is mixed with 5 kg of water at 80°C in a thermally insulated container. If latent heat of fusion = 3.36 × 10⁵ J/kg and specific heat of water = 4200 J/kg·K, determine the final state of the system.

A gas sample undergoes a process where pressure decreases linearly with volume: P = P₀ - kV, where k is a constant. For 1 mole of ideal gas at constant temperature, what is the work done when volume changes from V₁ to V₂?