2 projectiles are fired simultaneously from ground level with same initial speed (u).Both cover same horizontal distance of 160m on reaching the ground level .One of them reaches 6 sec prior to the other.Only gravitational acceleration g=10m/s squared governs the motion of both the projectile.Calculate u.[/B]
Range(horizontal distance)=u squared sin 2×theta/g= Ux cos theta ×time
Time=2u sin theta/g
U is initial velocity
Theta is the angle of projection
and T is the time taken by the projectile to reach ground level.
Note:vector u has 2 components which are Ux=u cos theta and Uy=u sin theta