Question

why does a desert cooler better on a hot dry day​

Answer 1

A desert cooler cools better on a hot dry day because on a hot dry day humidity is less,so the rate of evaporation increases which causes cooling effect.

Answer 2

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It is because the temperature is high and it is less humid on a hot dry day which enables better evaporation. High levels of this evaporation provide better cooling effects.

Thanks !!