Two small balls A and B each of mass m, are attched erighdly to the ends of a light rod of length d. The structure rotates about the perpendicular bisector of the rod at an angular speed `omega`. Calculate the angular momentum of the individual balls and of the system about the axis of rotation.

Explanation

Consider the situation shown in figure. The velocity of the ball A with respet to the centre O is ` V = (omega d)/(2) ` .
The angular momentum of the ball with respect to the axis is
`L_(1) = mvr = m ((omega d)/(2))((d)/(2)) = (1)/(4) m omega d^(2)` . The same the angular momentum ` L_(2)` of the second ball. The angular momentum of the system is equal to sum of these two angular momenta i.e., `L = 1//2 m omega d^(2)` .