Newton ’ s Third Law To every action , there is always an equal and opposite reaction .
For example , when you hold the ball , a force acts on the ball ( Action ), and an equal and opposite force acts on your hand ( Reaction ).
o
Action & Reaction forces always act on different bodies o o o
FAB = FBA
FAB : Force acting on A by B
FBA : Force acting on B by A o
Action & Reaction forces occur at the same instant
Conservation of Momentum o In an isolated system , the total momentum is conserved .
Example 1 . In a Spinning top , total momentum = 0 . For every point , there is another point on the opposite side that cancels its momentum .