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Two circular disc A and B with equal rad...

Two circular disc `A` and `B` with equal radii are blackened. They are heated to same temperature and are cooled under identical conditions. What inference do your draw from their cooling curves?

A

A and B have same specific heats

B

specific heat of A is less

C

Specific heat of B is less

D

Nothing can be said

Text Solution

Verified by Experts

The correct Answer is:
B

According to Newton's law of cooling rate of cooling is given by `((-dT)/(dt))=(eA sigma)/(mc)(T^(4)-T_(0)^(4))`
Where C is specific heat of material or `((-dT)/(dt)) prop 1/c`
i.e., rate of cooling varies inversely as specific heat, from the graph, for A rate of cooling is larger. therefore, specific heat of A is smaller.
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RESONANCE ENGLISH-HEAT TRANSFER-Exercise
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