# Hot or not?

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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