This page covers AFCAT Thermodynamics with complete concept notes, 18 graded practice MCQs, key points and exam-specific tips. Free to study.
18graded MCQs · easy to hard · full solution & trap analysis
A heat engine receives 1000 J of heat from a hot reservoir and releases 600 J to a cold reservoir in one cycle. What is the efficiency of the engine?
A gas absorbs 500 J of heat and expands against an external pressure, doing 200 J of work. What is the change in internal energy of the gas?
Which of the following is an intensive property of a thermodynamic system?
In an adiabatic process, 400 J of work is done on a gas. What is the change in internal energy of the gas?
A rigid container filled with an ideal gas is heated. Which thermodynamic process does this represent?
A system absorbs 500 J of heat and does 200 J of work on the surroundings. What is the change in internal energy of the system?
An ideal gas undergoes an isothermal process at 300 K. If the initial volume is 2 L and final volume is 8 L, what is the work done by the gas? (R = 8.314 J/(mol·K), n = 1 mol)
Which of the following statements correctly describes the second law of thermodynamics?
A rigid container holds 2 moles of an ideal gas at 400 K with internal energy 5000 J. The gas is heated until its temperature becomes 500 K. What is the work done by the gas?
For an adiabatic process of an ideal gas, which relation correctly represents the process?
An ideal gas expands from 1 m³ to 3 m³ at constant pressure of 100 kPa. Calculate the work done by the gas.
The molar heat capacity of a gas at constant volume (Cv) for a diatomic ideal gas is:
A heat engine receives 1000 J of heat from a hot reservoir and rejects 400 J to a cold reservoir in one cycle. What is the efficiency of the engine?
A system has internal energy of 8000 J. It absorbs 3000 J of heat and 2000 J of work is done on it. What is the final internal energy?
A gas undergoes an isothermal expansion from volume V₁ = 2 L to V₂ = 8 L at temperature T = 300 K. If the initial pressure is P₁ = 4 atm, calculate the work done by the gas (use ln(4) ≈ 1.39).
One mole of an ideal diatomic gas is heated at constant volume from 300 K to 600 K. Calculate the change in internal energy (R = 8.314 J/(mol·K), Cv = 5R/2 for diatomic gas).
A heat engine operates between two thermal reservoirs at temperatures TH = 500 K and TC = 300 K. If the engine absorbs 5000 J of heat from the hot reservoir, what is the maximum possible work output?
A cylinder containing 2 moles of ideal gas undergoes adiabatic compression. The initial temperature is T₁ = 300 K and final temperature is T₂ = 450 K. Calculate the work done on the gas (Cv = (5/2)R, R = 8.314 J/(mol·K)).