Question

Is moment of inertia a scalar quantity

Answer 1

Moment of inertia

1. The word inertia refers to resistance or obstacle. While only referring to magnitude, not direction.
2. If the sum of the product of the masses of the particles that make up the body and the squares of their perpendicular distances from the axis of rotation.
3. The moment of inertia is also known as an angular mass in classical mechanics.

The formula for the moment of inertia

$I=\underset{i=1}{\overset{n}{\sum m_i{r_i}^2}}[wherem=mass,r=dis\tan ce]$

Analyzing the formula

1. Sometimes it behaves as a scalar & sometimes as a vector.
2. Sometimes it depends on the directions and sometimes depends on the distribution of mass of the particles in the object.
3. Therefore, a moment of inertia is a tensor quantity.

Hence, the moment of inertia is not a scalar quantity. A moment of inertia is a tensor quantity