What Is the Expectation of Angular Momentum Components for a Spin 5 Particle?

doublemint
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Hello All,

Right now, I am trying to complete my QM assignment, but I am getting confused about the notation.

So, the generalized angular momentum operator is represented as \hat{J} and -j is the quantum # associated with the magnitude and m_{j} is the quantum # associated with the projection of the angular momentum projection.
Then given j=2, m_{j}=-2,-1,0,1,2
So now onto spin. The spin operator is \hat{S} and similar s is the magnitude of the spin and m_{s} is the projections. Then given s=1/2, m_{s}=1/2,-1/2
So far so good right?
Now what is confusing to me is this: the question is asking for the expectation of the three components of angular momentum of a spin 5 particle. Does it mean s=5 or j=5?

Another question is what does it mean by "the quantum number associated with the magnitude of the spin for a particle"? Are they asking for s?

Thanks
DoubleMint
 
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I think they discard the orbital angular momentum, so that j=s=5. The magnitude is usually seen as the eigenvalue of S2.
 
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