(a) Define an insulator.
(b) State three properties of an insulating materials
(c) A cold room has its walls measuring 10 m by 4 m. If the conditional
temperature is 5OC and the outer temperature is 28OC, calculate the total heat transmitted through the wall. (take U – factor to be 0.93W/m2K).
Candidates performed well in parts (a) and (b) of the question. The required response to part (c) of the question is given below:
Area = L x B
= 10 x 4
= 40m2
Temperature difference (TD) = 28OC - 5 OC = 23 OC
U = O.93 W/m2K
Q = A x U x TD = 40 m2 x O.93W/ m2K x 23 OC
= 855.6W.
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