In the mass spectrograph above, the goo in the source chamber contains
molecules of mass 
that are ionized to have charges of 
, 
or 
at the source. The particles then fall through a potential
of 
and enter the uniform 
field in the box.
a) Derive an expression for the radius 
at which a fragment of
charge-to-mass ratio of 
hits.
b) Use this expression to find for each of the three possible
ionization charges, and draw a picture of the bars produced on the
film to a reasonable scale.