Question

State and prove, principle of conservation of angular momentum explain it with example

Answer 1

When no external torque acts on the body , the net angular momentum of a rotting rigid body remains constant.
This is known as law of conservation of angular momentum.



Angular momentum L=I
Torque= dL/ dt
when on external torque acts on the system dL/dt
so, L=Iw

EXAMPLES
A ballet dancer can increase her angular velocity by folding her arms , as this decrease the moment if inertia

Answer 2

Answer:

The linear momentum and angular momentum of the body is given by →p=m→v and →l=→r×→p about an axis through the origin. The angular momentum →l may change with time due to a torque on the particle. ∴→l = constant, i.e. →l is conserved. ... its angular velocity will also change if there is no external torque