The moment of linear momentum is known as angular momentum. In other words the rotational analog of linear momentum is known as angular momentum
Consider a particle of mass m at a distance r from the axis of rotation. When a particle is in rotational motion about an axis, it has both linear velocity ‘v’ and angular velocity ‘ω’.
Angular momentum of the particle = linear momentum x perpendicular distance between
the particle and the axis of rotation or radius (r)
We know that momentum = mass × velocity
Substituting the value of momentum in the above equation we get,
Angular momentum = m v × r
we know that relation between Linear velocity and Angular velocity is defined as
Linear velocity (v) = Radius (r) x Angular velocity (ω)
Substituting the values we get
Angular momentum = m × (r. ω) × r
Therefore, the formula for Angular momentum is given as,
Angular momentum = mr2ω
The S.I. unit for angular momentum is kgm2s-1