Question

Why are exhaust fans fixed at a height and not near the stove

Answer 1

Hot air is produced near the stove. Now if you have studied gas laws, you will know that volume of gas increases with increase in temperature, which means that density of the gas decreases as volume is inversely proportional to density. And hence, weight of hot air is lesser than that of cold air, which will also be present in your kitchen. therefore, hot air tends to occupy the physically higher space, which means that hot air is present in more concentration above a certain height from the stove, for which reason, exhaust fans are fixed at a height and not near the stove.

Answer 2

exhaust fans are fixed at a height and not near the stove because if it is fixed near stove then it may put off the flame when stove is on