A projectile is fired at an angle of 450 with the horizontal. Elevation angle of the projectile at its highest point as seen from the point of projection is

Height of projectileH = u2sin2θ2g = u2sin24502g⇒ H = u24g ------(i)Range of projectile R = u2sin 2θg = u2sin 900g⇒R = u2g      tan α = HR2In ∆OAB = u24gu22g     tan α =12   ⇒ α = tan-1(12)