COMEDK · Physics · 12. Thermal Properties of Matter
The thickness of a metallic plate is 0.4 cm . The temperature between its two surfaces is \(20^{\circ} \mathrm{C}\). The quantity of heat flowing per second is 50 cal from \(5 \mathrm{~cm}^2\) area. In CGS system, the coefficient of thermal conductivity will be
- A 0.4
- B 0.6
- C 0.2
- D 0.5
Answer & Solution
Correct Answer
(C) 0.2
Step-by-step Solution
Detailed explanation
\(\begin{array}{ll}\text { } & \frac{Q}{t}=\frac{K A(\Delta \theta)}{l} \\ \Rightarrow & 50=\frac{5 \times 20 K}{0.4} \\ \Rightarrow & K=\frac{1}{5}=0.2\end{array}\)
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