# 3 Problems Due Tomorrow and We're lost

1. Jan 31, 2010

### GLRult

Weve been working as a group on campus now for a few hours and we're lost on these 3. Our teacher did a horrible job explaining this material and the book doesn't do any better of one.

A long, non-conducting, solid cylinder of radius 4.7 cm has a uniform volume charge density ρ = 2.1 µC/m^3.
a) What is the magnitude of the electric field at a radial distance of 6.5 cm from the axis of the cylinder?
b) What is the magnitude of the electric field at a radial distance of 2.8 cm from the axis of the cylinder?

Particle A proton with speed v = 3.00 multiplied by 105 m/s orbits just outside a charged sphere of radius r = 1.04 cm. What is the charge on the sphere?

Concentric Spheres Two charged concentric spheres have radii of 9.5 and 14.7 cm. The charge on the inner sphere is 3.98 multiplied by 10-8 C and that on the outer sphere is 2.00 multiplied by 10-8 C.

(a) Find the electric field at r = 11.7 cm.
(b) Find the electric field at r = 20.4 cm.

Section 24.6 Application of Gauss' Law to Symmetric Charge Distributions

Surface of Cube At each point on the surface of the cube shown in Fig. 24-25, the electric field is in the positive direction of z. The length of each edge of the cube is 3.2 m. On the top surface of the cube, Evec = (-34 N/C)k, and on the bottom face of the cube Evec = (+19 N/C)k . Determine the net charge contained within the cube.