Question

efficiency of heat engine is 15% . The engine takes 1.8×10^9 joules energy per min from its boiler. How much heat per min is wasted from it?

Answer 1

answer___

hope this helps!

Answer 2

Given :

efficiency of the engine is 15 % .

The engine takes 1.8 × 10⁹ J per minute .

This means that in 60 s engine takes 1.8 × 10⁹ J .

This means that in 1 s engine takes 1.8 × 10⁹ J × 60

= > 108 × 10⁹ J

We know that efficiency = M.A / V.R

= > 15/100 = W/( 3 × 10¹¹ )

= > 3/20 × 10¹¹ × 3 = W

= > W = 9 × 10¹⁰ × 5

= > W = 45 × 10¹⁰ J/s

Let heat be Q.

Q = W - w

= Q = 108 × 10¹¹ -  45 × 10¹⁰

= Q = 10¹⁰ ( 1080 - 45 )

= Q = 10¹⁰ × 1035

In 1 minute :

Q = 10¹⁰ × 1035 / 60

Q = 17.25 × 10¹⁰ J

ANSWER :

1.725 × 10¹¹ J