Question

the flywheel of motor has a mass of 300kg and a radius of gyration of 1.5m​

Answer 1

Given : The flywheel of motor has a mass of 300kg and a radius of gyration of 1.5m.

To find : Moment of inertia

Solution :

When an object is in angular motion, the mass elements in the body are located at different distances from the center of rotation.

The total moment of inertia is the sum of the moments of inertia of the mass elements in the body.

Radius of gyration of an object is the radius which would have the same moment of inertia if all the mass of the object was distributed on that radius.

Moment of inertia is given by =

$m {k}^{2}$

where k is the radius of gyration.

Therefore, Moment of inertia =

$300 \times {1.5}^{2}$

$675$

Moment of inertia = 675 kg m2

Your question was incomplete, but most probably the question may be "the flywheel of motor has a mass of 300kg and a radius of gyration of 1.5m. Find moment of inertia."