Question

On a hot day if you are sweating, you will feel cooler than on a cooler moist day. This is because
A) The evaporation of sweat on a cooler moist day raises the body temperature
B) On a cot moist day you lose less of energy
C) There is loss of energy when you sweat
D) The evaporation of sweat on a hot day causes more cooling

Answer 1

Sweating which is also called perspiration is defined as the production of fluids secreted by the sweat glands which are present in the skin of the mammals.

Complete answer:
Sweating is primarily responsible for thermoregulation which means that they help in maintaining and regulating the body's temperature. Sweating can be caused due to change in body temperature, or even the body's emotional state. Sweating usually occurs through the face, armpits, palms of hands and also the soles of the feet. Let us analyze the options to find out why on a day makes you feel cooler than a moist day.

Option A: The evaporation of sweat always decreases the body temperature. However, this evaporation is less during the moist days instead of a hot day.Therefore, this is the incorrect option.

Option B: Loss of energy is not associated with a moist day. Therefore, this is the incorrect option.

Option C: When the body sweats only a minimal amount of energy is lost. This has no relation to excess energy loss and even decrease in body temperature.Therefore, this is the incorrect option.

Option D: When it's a hot day the sweat on the body evaporates from the skin which decreases the body temperature and makes skin feel cooler. Also, evaporation decreases the body heat. Evaporation rate is low in humid or mist temperature while higher during the dry days. That is why we feel cool when the body sweats when it's hot and not during the humid days.Therefore, this is the correct option.

Thus, the correct answer is option (D) The evaporation of sweat on a hot day causes more cooling.

Note: There are two types of sweat glands in our body namely eccrine and apocrine gland of which the eccrine glands are located all over the body and apocrine glands are located at scalp, armpits and groin.