31. We denote the radius of the thin cylinder as R = 0.015 m. Using Eq. 23-12, the net electric field for r > R is given by Enet = Ewire + Ecylinder = + 2 0 r 2 0 r
where = 3.6 nC/m is the linear charge density of the wire and ' is the linear charge densi
32. To evaluate the field using Gauss law, we employ a cylindrical surface of area 2 r L where L is very large (large enough that contributions from the ends of the cylinder become irrelevant to the calculation). The volume within this surface is V = r2 L
33. In the region between sheets 1 and 2, the net field is E1 E2 + E3 = 2.0 105 N/C . In the region between sheets 2 and 3, the net field is at its greatest value: E1 + E2 + E3 = 6.0 105 N/C . The net field vanishes in the region to the right of sheet 3,
34. According to Eq. 23-13 the electric field due to either sheet of charge with surface charge density = 1.77 1022 C/m2 is perpendicular to the plane of the sheet (pointing away from the sheet if the charge is positive) and has magnitude E = /20. Using t
35. (a) To calculate the electric field at a point very close to the center of a large, uniformly charged conducting plate, we may replace the finite plate with an infinite plate with the same area charge density and take the magnitude of the field to be