A body of mass 2kg is projected from the ground with a velocity 20ms^(-1)at an angle 30^@with the vertical. If t_1 is the time in seconds at which the body is projected and t_2is the time in seconds at which it reaches the ground, the change in momentum in kgms^(-1)during the time (t_2- t_1) is

A body of mass 2kg is projected from the ground with a velocity 20ms^(

1.	A body of mass 2kg is projected from the ground with a velocity 20ms^(-1)at an angle 30^@with the vertical. If t_1 is the time in seconds at which the body is projected and t_2is the time in seconds at which it reaches the ground, the change in momentum in kgms^(-1)during the time (t_2- t_1) is
Answer» 40 `40sqrt3` `50 sqrt3` `60` ANSWER :B