# Is friction really independent of surface area? [duplicate]

All of the sources I read says that friction is independent of surface area, but when we throw a heavy object with large area from a certain height, it experiences more air drag, which is related to friction, but when we throw another object of equal mass and smaller surface area, it experiences less drag.

Also, a circular or spherical wheel like structure experiences less friction than a cubical block of equal mass and equal co-efficient of friction.

Can you explain me why it happens?