Question

At each point on the surface of the cube shown in figure, the electric field is parallel to the z axis. The length of each edge of the cube is 3.0 m. On the top face of the cube, the electric field is E = - 20 kˆ (N/C), and on the bottom face E = - 20 kˆ (N/C). Determine the net charge contained within the cube.

A) – 3.2 x 10^-9 C 

B) + 3.2 x 10^-9 C 

C) – 1.9 x 10^-10 C 

D) + 1.9 x 10^-10 C 

E) + 0.90 x 10^-9 C

Answer 1

Correct option is A) – 3.2 x 10^-9 C

Top:

Bottom:

There is no electric flux through the other sides.