A water-heater is covered with insulation boards over a total surface area of 3 m2. The inside board surface is at 75¬¨¬®‚Äö√†√ªC and the outside being at 20¬¨¬®‚Äö√†√ªC and the conductivity of material being 0.08 W/m K. Find the thickness of board to limit the heat transfer loss to 200 W ?$

A water-heater is covered with insulation boards over a total surface

1.	A water-heater is covered with insulation boards over a total surface area of 3 m². The inside board surface is at 75¬¨¬®‚Äö√†√ªC and the outside being at 20¬¨¬®‚Äö√†√ªC and the conductivity of material being 0.08 W/m K. Find the thickness of board to limit the heat transfer loss to 200 W ?$
A.	0.036 m
B.	0.046 m
C.	0.056 m
D.	0.066 m
Answer» E.

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