Homework Answers
heat loss = Q = 3kW = 3000 W
Heat transfer coefficient = U = 5 W K-1 m-2
Area = A = 6 m2
T1 = 20 0C
T2 = ?
Q = UA(T2-T1)
3000 = (5)(6)(T2-20)
T2-20 = 100
T2 = 100-20
= 120 oC
Correct temperature = (120 - 20) oC = 100 oC
Answer is D.
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