Question

What role does specific heat capacity play in a watermelon?

Answer 1

Watermelon contains 92% of water.  Since the specific heat capacity of water is very high 4200 J/(kg K), the specific heat capacity of watermelon is also high. The higher the specific heat of an object the more energy it requires to increase its temperature. So it takes a longer time to heat up, if the surroundings are supplying heat energy at a constant rate. That is why watermelon remains cool for a long time after removing it from a fridge on a hot day.

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