1. The problem statement, all variables and given/known data If a beam of hydrogen atoms in ground state are passed through an inhomogeneous magnetic field, into how many paths will the beam be split? Assume that the beam is moving towards the plane of this page and the magnetic field is directed in the upward direction in the plane of this page. 2. Relevant equations 3. The attempt at a solution It is known fact that naturally the beam will be divided into 2. What about the plane in which the 2 split beams exist. When I apply Flemings left hand rule, I find that it is in the horizontal plane. But the answer says, it is in the vertical plane.