A man stands on a rotating platform, with his arms stretched horizontally holding a 5 kg weight in each hand. The angular speed of the platform is 30 revolutions per minute. The man then brings his arms close to his body with the distance of each weight from the axis changing from 90cm to 20cm. The moment of inertia of the man together with the platform may be taken to be constant and equal to `7.6 kg m^2`:- What is his new angular speed? (Neglect friction.)

A man stands on a rotating platform, with his arms stretched horizontally holding a 5 kg weight in each hand. The angular speed of the platform is 30 revolutions per minute. The man then brings his arms close to his body with the distance of each weight from the axis changing from 90cm to 20cm. The moment of inertia of the man together with the platform may be taken to be constant and equal to 7.6 kg m^2 :- Is kinetic energy conserved in the process? If not, from where does the change come about?

Calculate the angular speed of the wheel making 240 revolutions per minute.

A perso is standing on a rotating platform wit his arms outstretched.Suddelny,he folds his hands near to his body.which of the following is correct?

A gramophone disc rotates at 60 revolutions per minute. A coin of mass 13 g is placed at the disc at a distance of 8.0 cm from the centre. Calculate centrifugal force on the coin.

Why is it dangerous to stand on the edge of the platform near the railway line when the train is passing by?

The speed of rotation of a person with some weights in his hands and standing on a rotating platform increases as he draws his arms close to his chest.Why?Explain.