Physics-
General
Easy
Question
The figure shows a system of two concentric spheres of radii r1 and r2 and kept at temperatures T1 and T2, respectively. The radial rate of flow of heat in a substance between the two concentric spheres is proportional to
- In
The correct answer is:
Consider a concentric spherical shell of radius r and thickness dr as shown in fig.
The radial rate of flow of heat through this shell in steady state will be 
Þ 
Which on integration and simplification gives
Þ 
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