What is Rotational Inertia?
Rotational inertia (moment of inertia) is a measure of how resistant an object is to changes in its rotational motion. It is the rotational equivalent of mass in linear motion. The value depends on both the total mass and how that mass is distributed around the axis of rotation. Engineers and physicists use rotational inertia to predict how objects respond to applied torques.
How to Calculate Rotational Inertia
Here is the formula:
[I = \frac{L}{\omega}]
Where:
- I is the rotational inertia (kg·m²).
- L is the angular momentum (kg·m²/s).
- ω is the angular velocity (rad/s).
Calculation Example
An object has an angular momentum of 30 kg·m²/s and an angular velocity of 15 rad/s.
[I = \frac{30}{15} = 2]
The rotational inertia is 2 kg·m².