NTA Abhyas JEE Main2020PhysicsRotational MotionPractice
A uniform thin hemispherical shall is kept at rest and in equilibrium on an inclined plane of angle of inclination θ = 30 o as shown in figure. If the surface of the inclined plane is sufficiently rough to prevent sliding then the angle α made by the plane of hemisphere with inclined plane is:
Options
- AValue of μ is needed
- B30 o
- C45 o
- D60 o
Correct answer
D. 60 o
Step-by-step solution
O is the centre of mass of the hollow hemisphere and is R 2 from C. f = m g sin θ ...(i) N - m g cos θ ...(ii) N × R 2 sin α = R R 2 cos α f ...(iii) ∴ tan θ = sin α 2 - cos α ⇒ α = 60 o