Perspiration cools the body because
[amp_mcq option1=”presence of water on the skin is cooling” option2=”evaporation requires latent heat” option3=”water has a high specific heat” option4=”water is a poor conductor of heat” correct=”option2″]
This question was previously asked in
UPSC NDA-1 – 2015
Perspiration cools the body through the process of evaporation. When sweat (water) evaporates from the skin surface, it changes from a liquid to a gas. This phase change requires energy, which is absorbed from the skin and underlying tissues. This energy absorbed is known as the latent heat of vaporization. By absorbing heat from the body, the evaporation process effectively cools the skin and helps regulate body temperature.
Evaporation of sweat cools the body because it requires latent heat, which is drawn from the body itself.