Question

Doctor advice to put strips of wet cloth on the forehead of a person having high temperature. Why?

Answer 1

Doctor advice to put strips of wet cloth on forehead of a person having high temperature.

Water from the wet cloth keeps on evaporating. To evaporate, the water requires energy. It takes this energy from the surrounding in the form of heat. Here, the surrounding refers to our body. It helps to cool our body and reduce the body temperature.

Answer 2

I am not completely sure if my answer is correct, but we learnt about evaporation this year. Evaporation causes cooling. When a liquid is evaporating, it's upper layer particles tend to gain kinetic energy from the surroundings and after gaining enough energy, they leave the liquid and covert into gaseous form, thus evaporating. Because they take up energy from the surroundings, the surrounding looses energy and the temperature decreases. Your question can be explained in this way. When the particles on the wet cloth evaporate, they take up enough energy from the surroundings to make the surroundings (here, the forehead of the person) cool. That's why if u remove the cloth after some time, and then you touch the forehead, you will feel it is cool. This is why the doctor advises to do this, so that the patient can recover from fever faster.
Hope this helped!!! :)