Free Thermodynamics MCQs with Answers
714 Thermodynamics MCQs from Physics, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Thermal equilibrium and heat explain how temperature and energy transfer are related, while molar specific heats describe the heat required by a gas at constant volume or constant pressure. The first law connects heat supplied, work done and change in internal energy, with sign conventions kept distinct from temperature changes.
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Read the Thermodynamics notesFree MDCAT chapter notes with key terms714 questions · page 27 of 36
- A. Water equivalent
- B. Temperature gradient
- C. Thermal capacity
- D. Specific heat
Explanation: Option C is correct. Thermal capacity, or heat capacity, is the overall amount of heat required to raise the temperature of a given mass…
Correct answer: Thermal capacity- A. 30g
- B. 80g
- C. 150g
- D. 1600g
Explanation: Option A is correct.Heat contained in waterQ=msΔT (s=1cal/gm/ o C) Q=80×1×(30−0)Q=2400Cal Then, heat gained by ice will be sameQ=2400Lf…
Correct answer: 30g- A. Mud is a good conductor of heat
- B. Mud is a superconductor of heat
- C. Mud is a bad conductor of heat
- D. Heat is first given out and then taken out
Explanation: Option C is correct. Mud is a bad conductor of heat, meaning it does not transfer heat efficiently.
Correct answer: Mud is a bad conductor of heat- A. Heat is given out
- B. Heat is taken out
- C. No change in temperature
- D. Heat is first given out and then taken out
Explanation: Option C is correct.The heat capacity is the amount of heat required to raise the temperature of an object or substance by one degree.
Correct answer: No change in temperature- A. 0 K
- B. 273 K
- C. -273 K
- D. -273°C
Explanation: Internal energy is proportional to translational <K.E> that is proportional to T.
Correct answer: 273 K- A. Heat and surroundings
- B. Heat and other forms of energy
- C. Heat and liquids
- D. Heat and chemical energy
Explanation: Thermodynamics is a fundamental branch of physics that deals with the principles governing the energy transformations and the…
Correct answer: Heat and other forms of energy- A. Remains constant
- B. Increases by a factor of 4
- C. Is also doubled
- D. Is diminished by a factor of 1/4
Explanation: To determine how pressure changes, we use the ideal gas law: PV = nRT. Initially, the pressure is P = nRT/V.
Correct answer: Remains constant- A. 40 cm
- B. 30 cm
- C. 32 cm
- D. 24 cm
Explanation: This is the following solution: (remember the formula to solve questions with the same format)
Correct answer: 30 cm- A. 40cal/°C
- B. 160 cal/°C
- C. 200 cal/°C
- D. 8 cal°C^-1
Explanation: Option D is correct.We know thatThermal Capacity= mcThermal capacity = 40 g x 0.2cal/g/°C = 8 cal/°C
Correct answer: 8 cal°C^-1- A. 20 J
- B. 45J
- C. 30J
- D. 50J
Explanation: Given from the graph:a to b: Isobaric expansion (constant pressure)Pa = 2 × 10³ PaVa = 10 × 10⁻³ m³Vb = 20 × 10⁻³ m³Work done: W₁ = P × ΔV…
Correct answer: 20 J- A. PdT
- B. PdV
- C. VdP
- D. P2Dv
Explanation: In an isobaric process, the pressure remains constant while the volume changes.
Correct answer: PdV- A. Only K.E
- B. Only P.E
- C. K.E and P.E both
- D. Only gravitational energy
Explanation: In the model of an ideal gas, the molecules are considered to be point particles that do not interact with each other except through…
Correct answer: Only K.E- A. Kinetic energy only
- B. Potential Energy
- C. Kinetic and potential energy
- D. None of these
Explanation: The internal energy of an ideal gas is determined by the kinetic energy of its particles.
Correct answer: Kinetic energy only- A. ∆UII > ∆UI
- B. ∆UI = ∆UII
- C. ∆UII < ∆UI
- D. Relation between ∆UI and ∆UII cannot be determined
Explanation: As internal energy is a state function therefore change in internal energy does not depends upon the path followed i.e.
Correct answer: ∆UI = ∆UII- A. Zero
- B. Negative
- C. Negligible
- D. Positive
Explanation: ∆W=P∆V, here ∆V is negative so ∆W will be negative. When a system undergoes a contraction of volume, the work done by the system will be…
Correct answer: Negative- A. -600J
- B. 0J
- C. 200J
- D. -200J
Explanation: The net work done by the gas in a cyclic process is equal to the area enclosed by the cycle on the P-V diagram.
Correct answer: 200J- A. 2 x 10^4 Joules
- B. 2 x 10^5 x 100 Joules
- C. 2x100 Joules
- D. 2 x 10^-5 x 100 Joules
Explanation: To calculate the work done by a gas expanding at constant pressure, use the formula W = P∆V.
Correct answer: 2 x 10^4 Joules- A. Process 3
- B. Process 2
- C. Process 1
- D. Equal in all processes
Explanation: Area of PV graph= W Area under process 1 > area under process 2 > area under process 3
Correct answer: Process 1- A. 2PV
- B. 1/2PV
- C. PV
- D. Zero
Explanation: Work done= Area enclosed by triangle ABC = 1/2AC x BC= 1/2 x (3V-V) x (3P-P)=2PV
Correct answer: 2PV- A. Free expansion
- B. An isothermal expansion
- C. Isobaric
- D. An expansion at constant temperature
Explanation: The equation W = P(V2-V1) is used to calculate work done during an isobaric process, where the pressure remains constant.
Correct answer: Isobaric