Phy 214 Quiz 13 February 8, 2008

1. The magnitude of the electric field associated with a large plate having a charge s per unit area is s/2e_o. The electric field lines are as shown below. If two such plates, one with charge s per unit area, the other - s per unit area, are placed parallel to one another the magnitude of the composite electric field is

a. s/e_o between the plates, zero outside

b. s/e_o between the plates, ±s/2e_o outside

c. zero both between and outside the plates

d. ±s/2e_o both between and outside the plates

e. none of the above
2. A metallic cube is given a net charge +Q.

How are the free charges distributed?

1. Uniformly throughout the cube's volume.

2. Uniformly distributed along the surface.

3. Along the surface, but concentrated at the

centers of the faces.

4. Along the surface, but concentrated at the

corners.

5. Along the surface, but concentrated at the edges.