A massless rod of length l = 1 m with a small mass m at the end is hinged at point A . Initially it is vertical while touching the block of mass M. A slight push sets the system in motion. If the smal

Question

A massless rod of length l = 1 m with a small mass m at the end is hinged at point A . Initially it is vertical while touching the block of mass M. A slight push sets the system in motion. If the small mass loses contact with the block at the instant when the rod makes an angle α = 3 0 ∘ with the horizontal then what is the speed of the block at that instant (in nearest integers) ? Friction should be neglected. ( g = 10 m / s 2 )

TestHub · Accepted Answer

u sin α = v The horizontal acceleration of the small mass and the block is zero, when they lose contact ℓ mu 2 c o s α ​ = mg cos α sin α ⇒ u = g ℓ sin α ​ v = sin α g ℓ sin α ​ = 1 m / s

Physics - Rotation Question with Solution | TestHub

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