Question

Can angular momentum be conserved?

Answer 1

Angular momentum is conserved in a system if net torque on the system is 0.

Explanation:

`d/dtvec L = vec tau` where `vec L` is net angular momentum and `vec tau` is net torque

So if net torque = 0
we get,
`vec tau = 0`

`=> d/dtvecL = 0`
no change in net angular momentum, hence it is conserved.