Question

Why there is a need of ventilator on the roof

Answer 1

It's because hot air is lighter than cold air.So it goes upwards in the room
And if there is a ventilator in the room ,the hot air in the room can move out from the room And our room will be cool.

Answer 2

Hi friend, The answer is :
Because hot air is lighter than cold air,so it goes upwards in the room and if there is a ventilator on the roof , then it will remove the hot air from the room, thus making the room cool.
Hope this helps. . . Cheers. . . .
If you understood from it well, then please please mark as the BRAINLIEST.
Thanks.