Question:
A person is comfortable while sitting near a fan in summer because :
ARate of evaporation increases
BThe fan provides free ventilation
CThe fan circulates air
DNone of these
Answer:
A. Rate of evaporation increases
Explanation:
- The speed at which evaporation takes place is called rate of evaporation. Or you may say it the other way as the amount of vapours formed per unit time is called as the rate of evaporation.
- Evaporation is the surface phenomenon in which the particles at the surface gain enough energy to turn into vapour. There is a number of factors that affect the rate of evaporation.
- 1. Temperature: The rate of evaporation increases in increasing the temperature of the liquid. When the temperature of the liquid is increased by heating it, more particles of the liquid get enough kinetic energy to get into the vapour state. This increases the rate of evaporation.
- 2. Humidity of Air: When the humidity of air is low then the rate of evaporation is high and water evaporated more readily. The wet clothes dry quickly under the conditions of low humidity of air this is because when the humidity is low, the amount of water vapour present in the air is small.