Question

A heat engine has a hot reservoir of 490°C and a cold reservoir of 210°C. What is the efficiency of the engine?

Answer 1

ec=(TH-TC)/TH

ec=(490-210)/490=57.1%

Answer 2

Efficiency is the measure of how efficient a process is. It is used to assess the ability of a process in avoiding waste energy, materials, money and time in doing a desirable output. It is calculated in thermodynamics as:

Efficiency = 1 - Tc / Th

Efficiency = 1 - 210 / 490
Efficiency = 0.57