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A hollow copper sphere S and a hollow co...

A hollow copper sphere S and a hollow copper cube C, both of negligible thin walls of same area, are filled with water at `90° C` and allowed to cool in the same environment. The graph that correctly represents their cooling is

A

B

C

D

Text Solution

Verified by Experts

The correct Answer is:
C
As `(d theta)/(dt)=(epsilon A sigma)/(mc) 4 theta^3 Delta theta`
For given sphere and cube `( epsilon A sigma)/(mc) 4 theta^3 Delta theta` is constant `(d theta)/(dt)` = constant.
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