1. For hydrogen atoms in a d state, sketch the orbital angular momentum with respect to the z axis. Use units of U along the z axis and calculate the allowed angles of L with respect to the z axis.
2. For a hydrogen atom in the 6f state, what is the minimum angle between the orbital angular momentum vector and the z axis?
3. The red line of the Balmer series in hydrogen (A = 656.5 nm) is observed to split into three spectral lines with A = 0.040 nm between two adjacent lines when placed in a magnetic ?eld B. What is the value of B if A is due to the energy splitting between two adjacent m/ states?