Question

ind the net rate of heat transfer by radiation from a skier standing in the shade, given the following. She is completely clothed in white (head to foot, including a ski mask), the clothes have an emissivity of 0.200 and a surface temperature of 10.0ºC , the surroundings are at −15.0ºC , and her surface area is 1.60 m^2 . (answer in W)

Answer 1

Q=116.37 W

Step-by-step explanation:

Given that

Emissivity ,ε= 0.200

Surface temperature ,T₁ = 10⁰ C = 283 K

Surrounding T₂ = - 15⁰ C = 258 K

Area ,A= 1.6 m²

The net heat transfer given as

`Q=\sigma A \varepsilon (T_1^4-T_2^2)`

σ = 5.67 x 10⁻⁸

The temperature should be in Kelvin.

Now by putting the values

`Q=5.67* 10^(-8)* 1.6* 0.2* (283^4-258^2)\ W`

Q=116.37 W

Therefore answer will be 116.37 W.