Air resistance force is the force of air pushing against a moving object. Air resistance force is a type of frictional force (refer to Chapter 5 of this unit). Like all frictional forces, the force of air resistance always opposes the motion of an object. Usually, the air resistance force is not very strong. When you walk, for example, you are affected by air resistance force, but it does not really slow you down. If you start running, the air resistance force will become more noticeable.
Air resistance force depends on the speed and the size of the surface area of a moving object.
