# Lagrangian & Noether's thm

1. Feb 28, 2007

### quasar987

I have this question here from last year's exam that goes

"Use Noether's theorem to show that the angular momentum is conserved when the lagrangian is invariant under rotations."

I just want to know if this is true in the most general case, or if there are some restrictions somewhere not mentioned in the question.

Thank you.

2. Mar 1, 2007

### dextercioby

Yes, you'd have to check for infinitesimal rotations.