# Electric Field Between Oppositely Charged Parallel Plates

• Soaring Crane

## Homework Statement

An infinite plane of charge with surface charge density sigma = 8.00 nC/m^2 lies in the yz plane at the origin, and a second infinite plane of charge with surface charge density sigma = -8.00 nC/m^2 lies in a plane parallel to the yz plane at x = 4.00 m. The electric field at x = 3.50 m is approximately

a.226 N/C
b.339 N/C
c.904 N/C
d.452 N/C
e.zero

## Homework Equations

E = sigma/epsilon_0 for oppositely charged parallel plates

## The Attempt at a Solution

E = sigma/epsilon_0 = (8.00*10^-9 C/m^2)/(8.85*10^-12) = 904 N/C ?

## Homework Statement

An infinite plane of charge with surface charge density sigma = 8.00 nC/m^2 lies in the yz plane at the origin, and a second infinite plane of charge with surface charge density sigma = -8.00 nC/m^2 lies in a plane parallel to the yz plane at x = 4.00 m. The electric field at x = 5.00 m is approximately

a.226 N/C
b.339 N/C
c.904 N/C
d.452 N/C
e.zero

See below.

## The Attempt at a Solution

If one draws a diagram for the E (and F) vectors, the vectors cancel each other out when outside the space between the plates, so it is 0?

Thanks.

It's all good. (I didn't check your arithmetic for the first one, but your method is correct.)