JEE Main 2021 · 24 February · morning · Single correct · +4 / −1
Match List I with List II.
Choose the correct answer from the options given below :
| List I | List II | ||
|---|---|---|---|
| (a) | Isothermal | (i) | Pressure constant |
| (b) | Isochoric | (ii) | Temperature constant |
| (c) | Adiabatic | (iii) | Volume constant |
| (d) | Isobaric | (iv) | Heat content is constant |
- (1) (a) - (ii), (b) - (iii), (c) - (iv), (d) - (i)
- (2) (a) - (ii), (b) - (iv), (c) - (iii), (d) - (i)
- (3) (a) - (iii), (b) - (ii), (c) - (i), (d) - (iv)
- (4) (a) - (i), (b) - (iii), (c) - (ii), (d) - (iv)
Answer and solution
Answer (1) (a) - (ii), (b) - (iii), (c) - (iv), (d) - (i)
Solution
Physics sir · 3 steps
Read the Greek prefix and you have the answer: iso means same, and the root tells you what stays the same.
- Read the names. Iso means equal. Thermal is temperature, choric is volume (from the Greek for space) and baric is pressure (as in barometer). Adiabatic means no heat passes through.
Process What stays fixed Match (a) Isothermal Temperature, Δ T = 0 (ii) (b) Isochoric Volume, Δ V = 0 (iii) (c) Adiabatic No heat exchanged, Q = 0 (iv) (d) Isobaric Pressure, Δ P = 0 (i) - Adiabatic check. In an adiabatic process the system is insulated, so Q = 0 and its heat content does not change. Its temperature can still change, because Δ U = -W.
- So. The matching is (a) - (ii), (b) - (iii), (c) - (iv), (d) - (i), which is option (1).
The idea to keep. Isothermal fixes T, isochoric fixes V, isobaric fixes P, and adiabatic fixes heat: Q = 0. Adiabatic does not mean constant temperature.
Answer from the NTA final answer key. Solution by PrepWiser.