A object moving in a straight line has linear momentum(\(\vec{P}\)) . When a object rotates about some axis, there is momentum associated with rotational motion called the angular momentum \(\vec{L}\) Just as net external force is required to change the linear momentum of an object a net external torque is required to change the angular momentum of an object. S.I. unit of angular momentum \(\vec{L}\) is kg m 2 s -1 Note: When net external torque is zero angular Momentum can be conserve Type of angular momentum The angular momentum is classified in following three types. Angular momentum of a particle about some point [caption id="attachment_22163" align="aligncenter" width="300"] Angular momentum of a particle about some point[/caption] Let Assume that a particle Q of mass m is moving with linear momentum \(\vec{P}\) = m\(\vec{v}\). Its angular momentum L about point O is defined as: \(\vec{L}\)= \(\vec{r}\) × \(\vec{P}\) ...