# physics

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A certain heat engine does 8.0 kJ of work and dissipates 8.00 kJ of waste heat in a cyclical process.

(a) What was the heat input to this engine?

(b) What was its efficiency?

• physics -

Heat input Q=W+Q₁ =
=8000+8000 = 16000 J
η=W/Q =8000/16000=0.5
η =50%

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