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Internal energy change in an isothermal process: evaluate the statement Statement: “There is no change in internal energy in an isothermal process.” Decide whether this is correct for an ideal gas.

Q: Internal energy change in an isothermal process: evaluate the statement Statement: “There is no change in internal energy in an isothermal process.” Decide whether this is correct for an ideal gas.

Concept/Approach For an ideal gas, internal energy depends only on temperature: ΔU = m cv ΔT. Isothermal ⇒ ΔT = 0 ⇒ ΔU = 0. Final Answer Agree — for an ideal gas, isothermal implies no change in internal energy.

Difficulty: Easy

Agree (true for an ideal gas)
Disagree (false even for an ideal gas)
True only if pressure is constant
True only at very low temperatures

Correct Answer: Agree (true for an ideal gas)

Explanation:

Concept/Approach

For an ideal gas, internal energy depends only on temperature: ΔU = m c_v ΔT.
Isothermal ⇒ ΔT = 0 ⇒ ΔU = 0.

Final Answer
Agree — for an ideal gas, isothermal implies no change in internal energy.

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