NTA Abhyas JEE Main2020PhysicsWork, Power and EnergyPractice
A body is projected at an angle of 60 ° with the horizontal. If its kinetic energy at its maximum height is 10 J , then the height at which its potential energy and kinetic energy have equal values is (consider potential energy at the point of projection to be zero)
Options
- Ahalf of the maximum height
- Btwo third of the maximum height
- Cone sixth of the maximum height
- Dinsufficient data to solve the problem
Correct answer
B. two third of the maximum height
Step-by-step solution
KE at maximum height 1 2 mu 2 cos 2 6 0 ∘ = 1 0 J 1 2 mu 2 = 4 0 J Mg H max = 3 0 J ...(i) When PE = KE ⇒ mgh = 2 0 = ...(ii) from (i) and (ii) h H max = 2 3