Question
Two spheres of the same external radius and made of the same material are heated to the same temperature one of them is hollow and the other is a solid sphere. Whose temperature will fall faster when cooled?
✓
Answer
Both have the same external area. For this reason the rate of cooling will be the same but the rate of fall of temperature is inversely proportional to the mass. Therefore the temperature of hollow sphere will fall faster than that of a solid sphere.
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