Question

The thickness of a metallic plate is 0.4 cm. The temperature between its two surfaces is `20^(@)C`. The quantity of heat flowing per second is 50 calories from `5cm^(2)` area. In CGS system, the coefficient of thermal conductivity will be
A. 0.2
B. 0.3
C. 0.4
D. 0.5

Answer 1

Correct Answer - A
We know that
`Q/t=(KA(Deltatheta))/t`
`50 = (5 xx 20K)/(0.4)` or `K=(50 xx 0.4)/(5 xx 20) = 0.2`