A flywheel having moment of inertia `20kgm^(2)` rotates about its axis with an angular velocity of `100rads^(-1)`. If the moment of inertia of the flywheel is reduced to `10kgm^(2)` without applying external torque, calculate the new angular velocity of the Flywheel.

Explanation

As no external torque acts on the flywheel therefore, angular momentum is conserved hence
`l_(1)omega_(1)=l_(2)omega_(2)`
`rArr omega_(2)=(l_(1)omega_(1))/(l_(2))=(20xx100)/(10)=200 rad s^(-1)`.