JEE Main202117 Mar 2021Morning ShiftPhysicsRotational MotionActual
The following bodies, 1 a ring 2 a disc 3 a solid cylinder 4 a solid sphere, of same mass m and radius R are allowed to roll down without slipping simultaneously from the top of the inclined plane. The body which will reach first at the bottom of the inclined plane is [Mark the body as per their respective numbering given in the question]
Correct answer
4
Step-by-step solution
M g s i n θ R = m k 2 + m R 2 α α = Rg sin θ k 2 + R 2 ⇒ a = g sin θ 1 + k 2 R 2 t = 2   s a = 2   s   g sin θ 1 + k 2 R 2 for least time, k should be least and we know k , is least for the solid sphere.