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The windshield of a car is defrosted by passing hot air at a temperature Ti =...

The windshield of a car is defrosted by passing hot air at a temperature Ti = 40C on its internal surface. The thermal conductivity coefficient of the windshield is 2.06 x10 ^ -5. The outside air temperature is Text = -10C. Calculate the amount of heat that crosses the surface of plastic windshield that is 4mm thick for 1 hour and a total area of 10500cm ^ 2
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Answer #1

Given,

T1 = 40 C = 313 Kelvin

T2 = -10C = 263 Kelvin
k = 2.06 x 10^(-5)

(thickness) = 4 x 10^(-3) m

t = 3600 s

Area A = 10500 cm2

Amount of heat that crosses through the area for 1 hour,

Q = [k.A.(T1 - T2).t]/

Putting the values we get,

Q = 973.499 Watts

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