Question

Why does a desert cooler cool better on a hot dry day

Answer 1

Here your answer
A desert cooler cool better in hot dry day because on hot dry day temperature is high and humidity is less.
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Answer 2

The cooling in desert is caused by evaporation . On a hot and dry day , the temperature is higher so rate of evaporation increases and humidity is less ( as it’s a dry day) so rate of evaporation increases. Thus , the evaporation rate overall increases ; therefore a desert cooler cools better on a hot and dry day .
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