the two rotates with a common angular velocity.

A disc of circumference of s is at rest at a point A on a horizontal surface when a constant horizontal force begins to act on its centre. Between A and B there is sufficient friction to prevent slipping and the surface is smooth to the right of B, AB=s. The disc moves from A [...]

Two identical spheres A and B are free to move and to rotate about their centres. They are given the same impulse J. The lines of action of the impulses pass through the centre of A and away from the centre of B, then A horizontal disc rotates freely about a vertical axis through its [...]

A constant external torque τ acts for a very brief period Δt on a rotating system having moment of inertia I. (i) The angular momentum of the system will change by τΔt (ii) The angular velocity of the system will change by (τΔt)/I. (iii) If the system was initially at rest, it will acquire rotational [...]

A horizontal disc rotates freely about a vertical axis through its central. A ring, having the same mass and radius as the disk is now gently placed on disc. After some time, the two rotates with a common angular velocity. A horizontal disc rotates freely about a vertical axis through its central. A ring having [...]