2006-08-24 04:19:26 · 21 answers · asked by johnjeeva2001 1 in Science & Mathematics ➔ Physics
This question is like-- "hum Chlormint kyon khaate hain" !!
2006-08-24 16:53:15 · answer #1 · answered by Dr.Gagan Saini 4 · 0⤊ 0⤋
Normally in hot weather when we sweat, the water (from sweat) gets vapourized and is mixed in the air. Heat is consumed (and thus, 'coolness' is produced) in the process of vapourization. In a few seconds the vapour pressure in the air just near your body - or in the lower part of your room - becomes high. Vapour pressure corresponds to the amount of water vapour present in the air. Less is the vapour pressure, more is the vapourization - and vice-versa.
When we use a fan, it basically moves the air hence carrying the vapour away and mixing it with a larger mass of air - which reduces the vapour pressure and increases evaporation. Thus, we feel cool.
It is to be noted that evaporation is always occurring through our body; even when we do not feel sweaty.
2006-08-24 08:38:52 · answer #2 · answered by Ankit 2 · 0⤊ 0⤋
The air currents from the fan moving over our skin make our sweat evaporate faster, and the evaporation has a cooling effect. That's why you feel cooler sitting under a fan.
2006-08-24 04:22:12 · answer #3 · answered by Anonymous · 3⤊ 0⤋
The reason is scientific and governed by laws of latent heat of vaporization which states that it takes 5400kcal/gm of latent heat to convert liquid to its vapor state at atmospheric presuure and temperature.
In a hot day we sweat.When we sit under the fan the mositure of sweat evaporates into vapor and takes 5400 kcal of heat per gram of sweat to vaporise.This heat is taken out of our body thus making it cool.And hence we feel cool when we sit below a moving fan in a hot day.
2006-08-28 03:28:28 · answer #4 · answered by Anirban RoyChoudhury 2 · 0⤊ 0⤋
On a hot day, we'll naturally feel uncomfortable. A fan helps cool us off, making us more comfortable
2006-08-24 04:28:13 · answer #5 · answered by D Gyroscope 2 · 1⤊ 0⤋
The air movement from the fan helps to dry the perspiration which cools the body.
2006-08-24 04:28:10 · answer #6 · answered by kiss 4 · 1⤊ 0⤋
you may sit under a tree or aircooler or still go in a indoor swimming pool to get off the heat and sweating of the hot day
2006-08-24 05:14:58 · answer #7 · answered by toliagoldstar 2 · 0⤊ 1⤋
It circulates the air in the room and makes things cooler.
2006-08-24 04:28:06 · answer #8 · answered by skaichic 1 · 0⤊ 0⤋
To thin the boundary layer adjacent to our skin to facilitate heat transder.
2006-08-26 21:50:30 · answer #9 · answered by zamir 2 · 0⤊ 0⤋
fan make air to move and this helps evaporation of sweet and we feel cool.
2006-08-24 20:00:57 · answer #10 · answered by eshaghi_2006 3 · 0⤊ 0⤋