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A refrigerator door is 150 cm high, 80 c...

A refrigerator door is 150 cm high, 80 cm wide, and 6 cm thick. If the coefficient of conductivity is 0.0005 `cal//cm s^@C` and the inner and outer surfaces are at `0^@C` and `30^@C`, respectively, what is the heat loss per minute through the door, in caloris?

Text Solution

Verified by Experts

Apply the equation of thermal conductivity
`Q=(kA(t_h-t_c)("time"))/(d)=(0.005(150xx80)(30^@-0^@)(60))/(4)`
`=1800` cal
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