A steam engine delivers 5.4×108 J of work per minute and services 3.6 × 109 J of heat per minute from its boiler. What is the efficiency of the engine? How much heat is wasted per minute?

Asked by Abhisek | 1 year ago |  179

1 Answer

Solution :-


Work done by the steam engine per minute, W = 5.4 x 108J

Heat supplied from the boiler, H = 3.6 x 109J

Efficiency of the engine 

\( \dfrac{Output\;Energy}{Input\; Energy}\)


η = \( \dfrac{W}{H}\)

\( \dfrac{ 5.4 \times 10^8}{(3.6 \times 10^9)}\)

On simplification, we get,

= 0.15

Therefore, the percentage efficiency of the engine is 15%

Amount of heat wasted = 3.6 x 109 – 5.4 x 108

We get,

= 30.6 x 108

= 3.06 x 109J

Hence, the amount of heat wasted per minute is 3.06 x 109J

Answered by Pragya Singh | 1 year ago

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