## Forces and Accelerations: F=ma

Theexplanation above is very simplistic. It ignores all other forcesapart from the applied force. Infact there will be other forces acting, most commonly friction, andwe must find the net force F before we use F=ma to calculate theacceleration.

The ball above is falling.The net force F is W-R. If m=5 Kg and R=20N then applying F=ma:

The block above is beingpulled along the ground. The resultant force F is P-R. If P=30N,R=10N and m=2 Kg then applying F=ma: