Friction is always there to slow things down
1) If an object has no force propelling it along it will always slow down and stop because of friction (unless you're in space where there's nothing to rub against).
2) Friction always acts in the opposite direction to movement.
3) To travel at a steady speed, the driving force needs to balance the frictional forces.
4) You get friction between two surfaces in contact, or when an object passes through a fluid (drag).
Resistance or "drag" from fluids (air or liquid)
Most of the resistive forces are caused by air resistance or "drag". The most important factor…