How to Calculate the Electric Field of an Infinite Plane at a Specific Point?

[maherelharake]

Homework Statement

An infinite plane (2y+z=3) has surface charge density of sigma=2 microC/m². Find the electric field at (0,0,2)m

Homework Equations

The Attempt at a Solution

Would this just be E=sigma/2*epsilon-naught? Would the answer just be 1 microC/m² over epsilon-naught?

 

[Mindscrape]

So that would be the right magnitude, but what about direction?

 

[maherelharake]

Isn't it just the direction normal to the plane? In this case would it be (0,2,1)?

 

[Mindscrape]

Right, and really you want a unit vector so divide by sqrt(5). Looks good to me.

 

[maherelharake]

I think both components are supposed to be negative, but either way I got it it now. Thanks.

 

[Mindscrape]

Oh right, well I suppose that, yeah, you will have the negative. I spaced that one out.

 

[maherelharake]

No problem. Thanks.