Two bodies A and B , collide as shown in figures a and b below .circle the true statement : (a) (b) They exert equal and opposite forces on each other in (a) but not in (b) They exert equal and opposite forces on each other in (b) but not in (a) They exert equal and opposite forces on each other in (a) and (b) The forces are equal and opposite to each others in a but only the component of the forces parallel to the velocities are equal in b .