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Most Important Selected Qs for JEE AdvancedPhysicsRotational Motion

A carpet runner is placed onto a long straight inclined plane parallel to the steepest line in the plane, from the bottom of the slope till its top. The carpet is thin and flexible, and it cannot slide down because of the friction, but it can easily be lifted, it does not stick to the plane. The top end of the carpet is rolled, a bit, and this hoop of carpet is released. The hoop rolls down the slope with greater and

Correct answer

2

Step-by-step solution

The rolled part of the carpet is a cylinder, and its mass is proportional to x . Applying conservation of mechanical (1+ 1 2 ) 1 2 ( x) ( d x d t )^2=( x) g x 2 energy, aligned & ( dx dt )^2= v ^2= 2 ~g x 3 & i.e. a_ carpet = g 3 aligned For the cylinder, 3 4 m v^2=m g x .e. a_ c y 1 = 2 g 3 t₁ t₂ = a_ cy 1 a_ carpet = 2

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