# Spin operator

1. Nov 6, 2012

### rubertoda

I should Use
the fact that in general the eigenvalues of the square of the angular momentum
operator is J(J + 1)h and show the spin of the electron.

I have J= L+S and J2 = L2+ S2
1. The problem statement, all variables and given/known data

But how could i find the spin of the electron

2. Nov 6, 2012

### dextercioby

Not really, J^2 = L^2 + S^2 +2 L.S. And post the whole text of your problem.

3. Nov 6, 2012

### rubertoda

Yes, i was sloppy. I meant that. But, I am asked to show the spin of the electron, by knowing that the eigenvalue of J2 is usually J(J+1)hbar...what do they mean?

sthg like solving for S in J^2 = L^2 + S^2 +2 L.S?

4. Nov 6, 2012

### rubertoda

So how to do this

5. Nov 6, 2012

### dextercioby

Can you, please, post the text of your problem, exactly as it appears in your book ?

6. Nov 6, 2012

### rubertoda

Calculate the square of the total spin operator and ﬁnd all its eigenvalues. Use
the fact that in general the eigenvalues of the square of the angular momentum
operator is J(J + 1)¯h
2
to ﬁnd the spin of the electron.

the firts one i have fixed..