Question

A boy is standing on a horizontal massless rotating wheel with hid hands stretched. Kinetic energy of the boy is 120J. If he now folded his hands then MI is reduced to 80%,then new K.E. of the boy is-

Answer 1

Answer:

new K.E. of boy is 150J.

Explanation:

Linear motion energy is straightforwardly corresponding to the mass of the article and to the square of its speed: K.E. = 1/2 m v2.

On the off chance that the mass has units of kilograms and the speed of meters every second, On the other hand rotational energy has units of kilograms-meters squared every second squared.

So if the boy folded his hands then M.I is reduced to 80%. Then a new K.E. of boy, Increases by 30 J. And total is 150J