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Class 11
Physics
Thermodynamics
a steam engine delivers 5 4 x 108 j of work per mi...

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

Answer:

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

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

Efficiency of the engine = Output energy / Input energy

∴ n = W / H

= 5.4 × 10⁸ / 3.6 × 10⁹

Hence, the percentage efficiency of the engine is 15 %.

Amount of heat wasted = 3.6 × 10⁹ - 5.4 × 10⁸

= 30.6 × 10⁸ = 3.06 × 10⁹ J

Therefore, the amount of heat wasted per minute is 3.06 × 10⁹ J.

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

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

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