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3 years ago

12

Suppose you walk into a sauna that has an ambient temperature of 48.0°C. (a) Calculate the rate of heat transfer in watts to you

by radiation given your skin temperature is 37.0°C, the emissivity of skin is 0.98, and the surface area of your body is 1.30 m2.

1 answer:

GenaCL600 [577]3 years ago

4 0

Answer:99.84 W

Explanation:

Given

Ambient temperature $T_{\infty }=48^{\circ}C\approx 321\ K$

Temperature of skin $T=37^{\circ}C\approx 310\ K$

Skin emissivity $\epsilon =0.98$

Surface area $A=1.30\ m^2$

Rate of heat transfer is $Q=\epsilon A\sigma (T_0^4-T^4)$

$Q=0.98\times 1.30\times 5.67\times 10^{-8}((321)^4-(310)^4)$

$Q=99.84\ W$

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Part b)

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Part c)

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As we know that acceleration is rate of change in velocity of the object

So here we know that

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at t= 1.1 s we have

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now the net force of the object is given as

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Part b)

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now the direction of the velocity is given as

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$\theta = -127.7 degree$

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