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What is the efficiency of a device that takes 400J of heat and does 120J of work while giving off 280 J of heat

User Sirrah
by
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1 Answer

3 votes

Answer:

30%

Step-by-step explanation:

Efficiency = useful work / heat absorbed x 100

= 120/400 x 100

= 0.3 x 100

= 30%

User Iiro
by
7.1k points