A newly proposed device for generating electricity from the sun is a heat engine in which the hot reservoir is created by focusing sunlight on a small spot on one side of the engine. The cold reservoir is ambient air at 20°C. The designer claims that the efficiency will be 60%. What minimum hot-reservoirtemperature, in °C, would be required to produce this efficiency?

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Q: 1. Suppose a woman does 500 J of work and -9400 J of heat transfer occurs into the environment in…

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