Heat does rise. ... When we heat air, the molecules jiggle and zip around faster, which causes them to spread out. When a mass of air takes up more space, it has a lower density. When you have a lower density fluid immersed in a higher density fluid, the lower density fluid rises and the higher density fluid falls
Answers & Comments
Heat does rise. ... When we heat air, the molecules jiggle and zip around faster, which causes them to spread out. When a mass of air takes up more space, it has a lower density. When you have a lower density fluid immersed in a higher density fluid, the lower density fluid rises and the higher density fluid falls