Question

How evaporation causes a cooling effect

Answer 1

Dear student,
as we know that liquid converts into vapours by absorbing heat during evaporation
thus, as the heat is used up in converting liquid into vapours, temperature decreases to produce cooling effect

Answer 2

Evaporation is the process of conversion of water (liquid) to the water vapor (gaseous state). When liquid changes to gaseous state it absorbed some heat or energy from surrounding that decrease the temperature of surrounding and causes cooling effect.  

One of the live example is sweating. In hot summer days, sweat evaporate causes cooling effect that balance the temperature of body.  

Hence, evaporation is effective process that balance our body temperature in hot sunny days.