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The normal body-temperature of a person ...

The normal body-temperature of a person is `97(@)F` . Calculate the rate at which heat is flowing out of this body through the clothes asssuming the following values. Room temperature `=47^(@)F` , surface of the body under clothes `=1.6m^(-2)` , condutivity of the cloth `=0.04Js^(-1)m^(-1)^(@)C^(-1)` , thickness of the cloth `=0.5cm`.

Text Solution

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The correct Answer is:
A, C
`K=0.04 J//m-S^(@)C,`
`A=1.6 m^(2)`
`(T_(1))=97^(@)F=36.10^(@)C`
``T_(2)=47^(@)F=8.330^(@)C`
`l=0.5cm=0.005m`
`(Q)/(T)=(kA((theta)_1-(theta)_2))/(l)`
`(0.04xx1.6xx(27.7))/(0.005)=356 J//s`
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