Ch. 19 Homework, Phy 132, Spring 1998, Tulane

19.1   (a) 17.5 nC    (b) 26.2 N/C    (c) 4.37 N/C    (d) 2.57*10^-3 N/C
       (e) 2.52*10^-3 N/C

19.4   (a) approximate the disk as infinite since the distance is small
           2.03*10^5 N/C
       (b) same as (a) above
       (c) treat the disk as a point charge, 2.54 N/C
       (d) treat the disk as a point charge, 2.54*10^4 N/C
           compare this to the exact result, 2.15*10^4 N/C

19.10  (a) 20 N m^2/C    (b) 17.3 N m^2/C

19.17  (a) 0.407 nC    (b) 0 N/C    (c) 0 N/C    (d) 984 N/C    (e) 366 N/C

19.20  (a) 40.7 nC    (b) 339 N/C (treating the cylinder as infinite)
       (c) 1000 N/C   (d) 1000 N/C    (e) 610 N/C

19.24  (a) 14.2 nC/m^2    (b) 4.45*10^-12 C

19.28  6.77*10^5 C

19.40  Add the E-fields of the two planes vectorially 
       (a) inside the two planes, 1270 i + 1470 j N/C
       (b) outside the two planes, -1270 i + 5870 j N/C

19.53  Add x-component of the E-fields due to 4 sides,
       kQx/(L^2/4+x^2)/sqrt(L^2/2+x^2)