Question

A fly wheel is rotating at a speed of 160rpm whose weight is 20kg and its centre of mass is at a distance of 0.01m from the axis of rotation calculate moment of inertia of the fly wheel.and the energy stored in the fly wheel

Answer 1

Answer: The moment of inertia of the fly wheel is $I = 0.001 kg-m^{2}$ and the energy stored in the fly wheel is 0.0084 J.

Explanation:

Given that,

Angular speed $\omega = 160 rpm$

$\omega = \dfrac{16\pi}{3}\ rad/sec$

Mass M = 20 kg

Radius R = 0.01 m

The moment of inertia of the fly wheel

$I = \dfrac{MR^{2}}{2}$

$I = \dfrac{20kg\times(0.01\ m)^{2}}{2}$

$I = 0.001 kg-m^{2}$

The energy stored in the fly wheel is

$K.E = \dfrac{1}{2}I\omega^{2}$

$K.E = \dfrac{1}{2}\times0.001 kg-m^{2}\times\dfrac{16\times3.14}{3}$

$K.E = 0.0084 J$

Hence, the moment of inertia of the fly wheel is $I = 0.001 kg-m^{2}$ and the energy stored in the fly wheel is 0.0084 J.