PROBLEMS TO BE WRITTEN UP AND TURNED IN AT RECITATION

     These problems are due at your first recitation meeting after Tue 03/01.
     Each 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. 

              HRW Problem Supplement #1 - CHAPTER 26  (10 points)

         66.  Two parallel-plate capacitors A and B are connected
              in parallel across a 600 V battery.  Each plate has
              area 80.0 cm^2 and the plate separations are 3.0 mm.
              Capacitor A is filled with air; capacitor B is
              filled with a dielectric of dielectric constant
              Kappa = 2.60.  Find the magnitude of the electric
              field within (a) the dielectric of capacitor B and
              (b) the air of capacitor A.  What are the free
              charge densities on the higher-potential plate of 
              (c) capacitor A and (d) capacitor B?
              (e) What is the induced charge density on the surface 
              of the dielectric which is nearest to the 
              higher-potential plate of capacitor B.


              HRW Problem Supplement #1 - CHAPTER 27 (10 points)

         10.  (a) The current density across a cylindrical conductor
              of radius R varies in magnitude according to the equation

                            J = J_0(1-(r/R))

              where r is the distance from the central axis.  Thus,
              the current density is a maximum J_0 at that axis (r=0)
              and decreases linearly to zero at the surface (r=R).
              Calculate the current in terms of J_0 and the
              conductor's cross sectional area A = (pi)R^2.
              (b) Suppose that, instead, the current density is a
              maximum J_0 at the cylinder's surface and decreases
              linearly to zero at the axis: 

                              J = J_0(r/R)

              Calculate the current.  Explain why the result is
              different from that in (a).