Spin-orbit energy in an atom. estimate the magnitude of the spin-orbit energy for an atomic electron in the hydrogen 2p state. (hint: from the vantage point of the moving electron, the nucleus circles it in an orbit with radius equal to the bohr radius for this state. treat the orbiting nucleus as a current in a circular wire loop and use the result from classical electromagnetism, b = 2km de for the b field at the center of loop with radius r and magnetic moment u. here, km = 10-7 n/a2 is the magnetic constant in sl units.)