The thickness of a metallic plate is $0.4 cm$ . The temperature between its two surfaces is ${20^o}C$. The quantity of heat flowing per second is $50$ calories from $5c{m^2}$ area. In $CGS$ system, the coefficient of thermal conductivity will be
A$0.4$
B$0.6$
C$0.2$
D$0.5$
Medium
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C$0.2$
c (c) $\frac{Q}{t} = \frac{{KA(\Delta \theta )}}{l}$
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