# Hot or not?

Classical Mechanics Level 1

The Sun puts out a steady stream of roughly $$4\times10^{26}$$ W of radiation and weighs about $$2\times10^{30}$$ kg, while the average human eats 2,000,000 calories (1 Calorie = 1,000 calories) or $$\approx$$ 8,000,000 Joules a day, most of which is radiated as heat.

Calculate $$P/m$$, the rate of heat radiation per unit mass for the Sun and for the human body. Approximately how many times greater is $$P/m$$ for the Sun, than for the human body?

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