Prove that the time rate of change of the angular momentum of a particle is equal to the torque acting on it.

Underline the correct alternative :- The rate of change of total momentum of a many-particle system is proportional to the external force // sum of the internal forces on the system.

Find the components along the x, y, z axes of the angular momentum 1 of a particle, whose position vector is r with components x, y, z and momentum is p with components p_x,p_yand p_z . Show that if the particle moves only in the x-y plane the angular momentum has only a z-component.

How torque is related to angular momentum?

Derive the expression for angular momentum of a particle in two dimensions for in a plane).