Question

A flywheel has its moment of inertia tripled and angular velocity doubled.

The energy stored in it increase by a factor of ?​

Answer 1

energy stored in flywheel , E = $\frac{1}{2}I\omega^2$

where I is moment of inertia of flywheel and $\omega$ is angular velocity of it.

a/c to question,

moment of inertia tripled and angular velocity doubled.

e.g., I' = 3I and $\omega'=2\omega$

so, energy sorted in flywheel is, E' = 1/2 I'$\omega'^2$

= 1/2 × 3I × 4$\omega^2$

= 12 × $\frac{1}{2}I\omega^2$

= 12E

hence, energy stored in it increases by a factor of 12.