A body at rest breaks into two pieces of equal masses. The parts will move

Options

A. move in the same direction with equal speeds
B. move in any direction with any speed
C. move in opposite direction with equal speeds
D. move in opposite direction with unequal speeds

Answer

C

Explanation

As `F_(ext)=0` , hence `vec(P)_(1)+vec(P)_(12)` =constant
Because the system was at rest initally, hence
`vec(p)_(1)+vec(p)_(2)=0` or `vec(p)_(2)=-vec(p)_(1)` or `m_(2)vec(v)_(2)=-m_(1)vec(v)_(1)` Because `m_(1)=m_(2)` hence `vec(v)_(2)=-vec(v)_(1)` .