Weight
The force of gravity acting on the mass of an object
Weight =
mass x (9.8 m/s^2)
Normal Force
The upward force acting on an object on a surface; the normal force is perpendicular to the surface on which the object is sitting
Tension (T)
A force acting on a rope. When a rope is taut there is tension in the rope
Friction (F)
A resistive force that opposes motion