Question

A manufacturer claims to have a heat engine capable of developing 20 h.p. by receiving heat input of 400 kcal/mt and working between the temperature limits of 227° C and 27° C. His claim is

Answer 1

Answer:

claim is false

Explanation:

Output = 20 h.p = 14.914 Kw

input = 400 Kcal/min = 27.8932

Higher temperature ( T ) = 227° C = 273 + 227 = 500°C

Lower temperature ( t ) = 27° C =  273 + 27 = 300°C

Ideal coeffiecient of performance = $1 -\frac{t}{T } =1 - \frac{300}{500 }$   = 0.4

Actual cop = output /input = 14.914/27.8932   = 0.532

Here the actual cop is greater than ideal which is not possible.

Therefore his claim is false