Comparing Cooling Rates of Solid and Hollow Spheres

AI Thread Summary
When comparing the cooling rates of solid and hollow spheres of the same radius heated to the same temperature, the initial cooling rates may appear similar. However, the hollow sphere has a smaller heat capacity, allowing it to cool at a faster rate over time. Both spheres emit the same power at the same temperature, but the hollow sphere's lesser energy content leads to quicker cooling. This discussion highlights the importance of heat capacity in determining cooling rates. Ultimately, the hollow sphere cools faster than the solid sphere.
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There are two sphere of same radius but one is solid and other is hollow. Both are heated to same temperature(greater than room temperature). which will cool at faster rate?

I think both the spheres will cool at same rate since hollow sphere can't loose it's heat inside it (because internal temperature is also same as that of sphere) so both the spheres have same sink so they should cool at same rate.
however after little time their rate should vary because hollow sphere may have lesser energy..
IS my explanation correct?
 
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You are right: at the same temperature both emits the same power. But the hollow one has smaller heat capacity, so - emitting the same power it cools faster.
 


xts said:
You are right: at the same temperature both emits the same power. But the hollow one has smaller heat capacity, so - emitting the same power it cools faster.

OK!
thanks for confirming...
 
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