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First law at constant volume: decide correctness of the statement Statement: “When a gas is heated at constant volume, the heat supplied increases the internal energy of the gas.”

Q: First law at constant volume: decide correctness of the statement Statement: “When a gas is heated at constant volume, the heat supplied increases the internal energy of the gas.”

Concept/Approach At constant volume, boundary work is zero: W = ∫ p dV = 0. First law: Q = ΔU + W ⇒ Q = ΔU. Heat supplied raises internal energy. Final Answer Agree — the heat at constant volume increases internal energy.

Difficulty: Easy

Agree (true statement)
Disagree (false statement)
True only for ideal gases
False unless pressure is constant

Correct Answer: Agree (true statement)

Explanation:

Concept/Approach

At constant volume, boundary work is zero: W = ∫ p dV = 0.
First law: Q = ΔU + W ⇒ Q = ΔU. Heat supplied raises internal energy.

Final Answer
Agree — the heat at constant volume increases internal energy.

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