Question

why do we feel comfortable while sitting under fan during summer

Answer 1

Because fan promotes air flow which helps in the regulation of temperature on our body surface and makes us feel cool.

Answer 2

In summer our body gets depressed and needs of a lot of energy to do work. After doing any work our body also needs some relaxation to cure out the energy the had gone so we feel comfortable sitting under the fan during summer. I hope this would help you.