Problems from HRW Problem Supplement #1 (6th edition)
Chapter 26

53.  A certain parallel-plate capacitor is filled with
     a dielectric for which Kappa = 5.5.  The area of
     each plate is 0.034 m², and the plates are
     separated by 2.0 mm.  The capacitor will fail
     (short out and burn up) if the electric field 
     between the plates exceeds 200 kN/C.  What is the
     maximum energy that can be stored in the capacitor?

66.  Two parallel-plate capacitors A and B are connected
     in parallel across a 600 V battery.  Each plate has
     area 80.0 cm² 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 sigma on the higher-potential
     plate of (c) capacitor A and (d) capacitor B?
     (e) What is the induced charge density sigma' on
     the surface of the dielectric which is nearest to
     the higher-potential plate of capacitor B.

74.  The figure for this problem is Fig. 26-17, with
     the dielectric in that figure being replaced with
     a piece of copper.  A slab of copper of thickness
     b is thrust into a parallel-plate capacitor of
     plate area A; it is exactly halfway between the 
     plates.  (a) What is the capacitance after the
     slab is introduced?  (b) If a charge q is
     maintained on the plates, what is the ratio of
     the stored energy before to that after the slab
     is inserted?  (c) How much work is done on the 
     slab as it is inserted?  Is the slab sucked in
     or must it be pushed in?

Problems from Fishbane, Gasiorowicz, and Thornton
(2nd edition) Chapter 26

58.  By measuring the capacitance and voltage of a
     capacitor containing a dielectric with
     dielectric constant 3.1, the free charge on
     the capacitor is measured to be 2.9 microC.
     What is the induced charge?