JEE Main · 2023 · 29 Jan 2023 · Shift 1 · Heat & Thermodynamics

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Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : If dQ and dW represent the heat supplied to the system and the work done on the system respectively. Then according to the first law of thermodynamics .

Reason R : First law of thermodynamics is based on law of conservation of energy.
In the light of the above statements, choose the correct answer from the option given below :
  1. (A)A is correct but R is not correct
  2. (B)A is not correct but R is correct
  3. (C)Both A and R are correct and R is the correct explanation of A✓ Correct
  4. (D)Both A and R are correct but R is not the correct explanation of A

Answer: (C)

Solution

When denotes the work done on the system, the first law of thermodynamics is , which rearranges to , exactly as asserted. This law is a statement of the conservation of energy, applied by accounting for heat, internal energy and work. Both statements are correct and the reason is the correct explanation of the assertion.

JEE Main · 2023 · 29 Jan 2023 · Shift 1 · Single correct option

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