When a body on Earth is in motion, there are forces that counteract the motion of that body. One of the most dominant opposing force is friction. Friction arises when two objects come into contact, impeding the motion of one object over another.

However, air resistance, also known as drag, comes into play when a body is moving through a fluid, such as air or water. Air resistance opposes the motion of a moving body, particularly when the speed is relatively high. Fluid dynamics play a crucial role in determining the magnitude of drag on an object moving in a fluid medium.

Other opposing forces include gravitational forces acting against an upward motion or rolling resistance encountered by objects moving on surfaces due to irregularities and deformation of the surface material.