There are two spherical balls A and B of the same material with same surface finish but the radius of A is half than of B. If A and B are heated to the same temperature and allowed to cool then :

There are two spherical balls A and B of the same material with same s

1.	There are two spherical balls A and B of the same material with same surface finish but the radius of A is half than of B. If A and B are heated to the same temperature and allowed to cool then :
Answer» RATE of cooling of both is same rate of cooling of A is four times that of B rate of cooling of A is twice that of B rate of cooling of A is `1//4` time that of B. Solution :Rate of cooling `prop` area of BODY. `RARR""` rate of cooling `prop"(radius)"^(2)`. `:.` since radius of A is `1/2` od radius of sphere B. `:.` rate of cooling of A is `1/4` of rate of cooling of sphere B. Thus CORRECT choice is (d).

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There are two spherical balls A and B of the same material with same surface finish but the radius of A is half than of B. If A and B are heated to the same temperature and allowed to cool then :

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