1. The problem statement, all variables and given/known data one electron atom;l=1;a given magnetic field direction. Find possible directions of total angular momentum,J. 2. Relevant equations Z-axis is the direction of magnetic field; j=l+-1/2=3/2 or 1/2;mj=-j,-j+1,....,j-1,j;Jz=mjh/2p. 3. The attempt at a solution j=3/2 gives 4 directions and j=1/2 gives 2 directions.But in both the cases,Lz=mlh/2p and Sz=msh/2p are not satisfied for any ml(-1,0,1) and ms(-1/2,1/2).I learnt that L and S are space quantized. Isn't it true? Why aren't the three simultaneously space quantized? I also learnt that direction of magnetic field can be taken as Z-axis,so here,Z-axis of the three is same. Thanks for the reply.