An unknown charged particle is fired into an apparatus with a controllable magnetic field.  The animation shows a top view of the apparatus with the green arrow representing the velocity and the blue arrow the force. The magnetic field points into or out-of  the plane of view depending on the sign of B_z.  That is, the z axis is directed perpendicular to the computer monitor.  Enter a field value with magnitude less than 5 mT and press the play button whenever you wish to change the field.  Observe the force vector on the particle.  Determine the charge to mass ratio of the particle by studying the dynamics.  Time is measured in seconds and distance in cm.   Start