GATE ME 2021 Set 1 — Question 21

MCQ+1 / -0.33EasyCarnot Cycle & EntropyLaws & PropertiesThermodynamicsPower Cycles

Thermodynamics → Laws & Properties → Carnot Cycle & Entropy

Last updated 5 September 2026

Question

In which of the following pairs of cycles, both cycles have at least one isothermal process?

Correct answer (B) Carnot cycle and Stirling cycle Solution The Carnot cycle consists of two reversible isothermal processes and two reversible adiabatic (isentropic) processes. The Stirling cycle consists of two reversible isothermal processes and two reversible constant-volume (isochoric) processes with regeneration. Other cycles like Otto, Diesel, and Brayton do not contain isothermal processes in their ideal air-standard forms. Turn this into a strength. Explore AI-powered practice and doubt support with Success Tracker.

Review answer and solution without JavaScript

Interactive answer checking needs JavaScript. The published solution is available below.

Correct answer (B) Carnot cycle and Stirling cycle Solution The Carnot cycle consists of two reversible isothermal processes and two reversible adiabatic (isentropic) processes. The Stirling cycle consists of two reversible isothermal processes and two reversible constant-volume (isochoric) processes with regeneration. Other cycles like Otto, Diesel, and Brayton do not contain isothermal processes in their ideal air-standard forms.

Continue learning with Success Tracker

Use Success Tracker to ask about the reasoning, then try another GATE ME question to check your understanding.

AI-powered practice· Unlimited practice on eligible plans

PYQs with solutions: Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
Practice that adapts: Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
AI doubt support: Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.

Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.

This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.