Four spheres A, B, C and D are of same radius but made of different metals. Their densities are in r

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10-2.Transmission of Heat

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Four spheres $A, B, C$ and $D$ are of same radius but made of different metals. Their densities are in ratio $6 : 3 : 4 : 5$ and specific heats are in ratio $2 : 5 : 4 : 6$ . These are initially kept at the same temperature and placed in the same surroundings. The sphere which has the slowest rate of cooling is

A

$C$

B

$B$

C

$D$

D

$A$

Solution

$\mathrm{R}_{\mathrm{F}}=\frac{\mathrm{d} \theta}{\mathrm{dt}} \propto \frac{\mathrm{A}}{\mathrm{ms}}$

$\mathrm{R}_{\mathrm{F}} \propto \frac{1}{\mathrm{ms}}$

Standard 11

Physics

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