Figure shows a system of two concentric spheres of radii r₁ and r₂ and kept at temperatures T₁

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10-2.Transmission of Heat

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The figure shows a system of two concentric spheres of radii $r_1$ and $r_2$ and kept at temperatures $T_1$ and $T_2$, respectively. The radial rate of flow of heat in a substance between the two concentric spheres, is proportional to

A

$\frac{{\left( {{r_2} - {r_1}} \right)}}{{\left( {{r_1}{r_2}} \right)}}$

B

$\ln \left( {\frac{{{r_2}}}{{{r_1}}}} \right)$

C

$\frac{{\left( {{r_1}{r_2}} \right)}}{{\left( {{r_2} - {r_1}} \right)}}$

D

$\left( {{r_2} - {r_1}} \right)$

Solution

$H = k4\pi {r^2}\frac{{dT}}{{dr}} = {\text{constant}}$

Standard 11

Physics

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