PROBLEMS TO BE WRITTEN UP AND TURNED IN AT RECITATION

     This problem is due at your first recitation meeting after Wed 10/17.
     The problem should be written on a single sheet of paper (front and back), 
     or if multiple sheets are used, staple them together.  For full credit,
     the work must be neat, with clearly labeled diagrams.  The labels must
     be in BOTH words and symbols.  For each part of the problem, you must 
     BRIEFLY explain your strategy in words, as well as neatly showing your 
     physics equations and math, with proper units. 

            Problem from Wolfson (3rd edition) Chapter 30.

            68.  A solid conducting wire of radius R runs parallel
                 to the z axis and carries a current density given
                 by J_0(1-(r/R)) in the +z direction, where J_0
                 is a constant and r is the radial distance from
                 the wire axis.  Find expressions for
                 (a) the total current in the wire, (5 points)
                 (b) the magnetic field strength for r > R (5 points), and
                 (c) the magnetic field strength for r < R (10 points).