NTA Abhyas JEE Main2020PhysicsMotion in Two DimensionsPractice
A ball is projected from the ground at an angle of 45 o with the horizontal surface. It reaches a maximum height of 120 m and returns to the ground. Upon hitting the ground for the first time, it loses half of its kinetic energy. Immediately after the bounce, the velocity of the ball makes an angle of 30 o with the horizontal surface. The maximum height it reaches after the bounce (in meters) is _____________.
Correct answer
30.00
Step-by-step solution
H 1 = u 2 sin 2 45 o 2 g = 120 ⇒ u 2 4 g = 120 .....(i) when half of kinetic energy is lost v = u 2 H 2 = u 2 2 sin 2 30 o 2 g = u 2 16 g ......(ii) From (i) and (ii) H 2 = H 1 4 = 30 m o n 30.00