Q.
An ideal gas heat engine operates in Carnot cycle between 227°C and 127°C. It absorbs 6 × 10⁴ cal of heat at higher temperature. Amount of heat converted to work is :
A) 2.4 × 10⁴ cal
B) 3.6 × 10⁴ cal
C) 1.2 × 10⁴ cal
D) 6.4 × 10⁴ cal
Explanation
[Solution from source] η = 1 − T₂/T₁ = 1 − 400/500 = 0.2 (temperatures in kelvin). W = 0.2 × 6 × 10⁴ = 1.2 × 10⁴ cal. Using Celsius temperatures or the rejected heat (4.8 × 10⁴ cal) gives the wrong choices. Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.