Question

how is a hot cup of tea with thermal energy cools down

Answer 1

Temperature is the measure of energy or we can say thermal energy which is due to heat. We know that heat flows from higher temperature to lower temperature so as to set it self in stable state and every body in the universe tries to reach the stable state. So here in this case the temperature of the tea is more as compared to the surroundings hence the temperature will start to flow from tea to surrounding hence doing so will reduce the temperature of the tea. This process will happen till the temperature of the tea becomes equal to the Surroundings to reach equilibrium. This is how that tea becomes cool.

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