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Assume that the total surface area of a human body is `1-6m^(2)` and that it radiates like an ideal radiator. Calculate the amount of energy radiates per second by the body if the body temperature is `37^(@)C` . Stefan constant `sigma` is `6.0xx10^(-s)Wm^(-2)K^(-4)` .

Text Solution

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`A=1.6 m^2,T=37^(@)C=310^(@)K`
`s=6.0xx10^(-8)W//m^2K^4`
`Energy radiatead per sec `
`=AST^4=1.6xx6xx10^(-8)xx310^4`
`8865801xx10^(-4)=886.58`
`=887J`.
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  11. A copper sphere is suspended in an evacuated chamber maintained at 300...

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  13. A cylinderical rod of length 50cm and cross sectional area 1cm^(2) is ...

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  14. One end of a rod length 20cm is inserted in a furnace at 800K. The sid...

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  15. A calorimeter of negligible heat capacity contains 100cc of water at 4...

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  18. A metal ball of mass 1kg is heated by means of a 20W heater in a room ...

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