Question 902: Thermodynamics & KTG

Question

The temperature difference between two sides of an iron plate, $$1.8 \mathrm{~cm}$$ thick is $$9^{\circ} \mathrm{C}$$. Heat is transmitted through the plate $$10 \mathrm{k} \mathrm{cal} / \mathrm{sm}^2$$ at steady state. The thermal conductivity of iron is

Accepted Answer

$$\begin{aligned}
& \frac{Q}{A t}=\frac{k \Delta 	heta}{d} \
& 	herefore 10=k 	imes \frac{9}{1.8 	imes 10^{-2}} \
& 	herefore \quad k=\frac{18 	imes 10^{-2}}{9}=2 	imes 10^{-2} \mathrm{kcal} / \mathrm{mS}^{\circ} \mathrm{C}
\end{aligned}$$

Answer

$$0.02 \frac{\mathrm{kcal}}{\mathrm{ms}^{\circ} \mathrm{C}}$$

Answer

$$0.04 \frac{\mathrm{kcal}}{\mathrm{ms}{ }^{\circ} \mathrm{C}}$$

Answer

$$0.05 \frac{\mathrm{kcal}}{\mathrm{ms}^{\circ} \mathrm{C}}$$

Answer

$$0.004 \frac{\mathrm{kcal}}{\mathrm{ms}{ }^{\circ}}$$

Thermodynamics & KTG

The temperature difference between two sides of an iron plate, $1.8 \mathrm{~cm} thick is 9^{\circ} \mathrm{C}. Heat is transmitted through the plate 10 \mathrm{k} \mathrm{cal} / \mathrm{sm}^2$ at steady state. The thermal conductivity of iron is

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