The equation of motion of a projectile are given by x = 36 t m and 2y = 96 t - 9.8 t2 m. The angle of projection is

It is given that, x = 36 t∴  vx=dxdt=36 ms-1 and y=48t-4.9t2∴  vy=48-9.8t At t=0 ,vx=36 ms-1 and vy=48 ms-1So, angle of projection,  θ=tan-1vyvx               =tan-14836=tan-143or         θ=sin-145