Question

An ideal gas heat engine operates in Carnot cycle between 227∘C and 127∘C. It absorbs 6×104 cals of heat at higher temperature. Amount of heat converted to work is:-

Answer 1

The amount of heat rejected to sink at lower temperature is 1.2 K.cal

Explanation:

The efficiency of heat engine is

η = ​W  /  Q  1

η = 1 −   T  2  / T 1

Here,

Q  1  ​= heat absorbed from the source of heat = 6 k.cal

T  1  = temperature of source = 227 + 273 = 500 K

T2  = temperature of sink = 127 + 273 = 400 K

Hence  

W  / 6   = 1 - 400 / 500

W / 6 = 1/5

W = 1.2 K.cal

Hence the amount of heat rejected to sink at lower temperature is W = 1.2 K.cal