Question

why does a dessert cooler cool better on a hot dry day

Answer 1

Hey!

On a hot day, the temperature is high and humidity is low. The rate of Evaporation increases with increase in temperature and decrease in humidity.

A desert cooler functions on the principle of Evaporation. The water takes heat from from the hot desert cooler and evaporates. The Evaporation of water cools the pads and the circulating water. As a result, the incoming air also gets cooled down.

Hope this helps ✌✌

Answer 2

The particles of liquid in desert cooler absorb energy from the surrounding to regain the energy lost during evaporation. In summer this is fast. Hence desert cooler cool better in a hot dry day.