Physics-
General
Easy
Question
Two circular discs A and B with equal radii are blackened. They are heated to some temperature and are cooled under identical conditions. What inference do you draw from their cooling curves?
and 
have same specific heats
- Specific heat of is less
- Specific heat of is less
- Nothing can be said
and have same specific heats
is less
is less
The correct answer is: Specific heat of is less
According to Newton’s law of cooling, rate of cooling is given by
Where c is specific heat of material.
or 
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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