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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
Rate of cooling –
`(dQ)/(dt)=-(e A sigma)/(mc)(theta^4 - theta_0^4)`
- ve sign indicate that temperature decreases.
`implies (dQ)/(dt) prop 1/c`
For A, rate of cooling is large, specific heat of A is smaller.
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