# When conservation does not apply

im just talking in general about conservation of linear momentum, angular momentum, mechanical energy, etc.

So, for angular momentum, if angular momentum is constant, then initial angular momentum = final angular momentum.

But, what if there is a net torque? How do you take that into account when calculating the final angular momentum?

It's quite analogous to linear momentum and linear force. When a torque is applied over a certain amount of time, it adds angular momentum. For example, imagine pedaling a bicycle. The motion of the wheels remains mostly constant, then once you start pedaling it speeds up, increasing angular momentum.

In general, torque can be thought of as a rate of change in angular momentum.

Claude Bile