# Need some help with this homework -- Conducting Spheres and Charge

1. Aug 28, 2015

### Rene Manzano

• Poster has been reminded by the Mentors that they need to use the HH Template and show their work
Hi, I need some help with this homework from my Electromagnetism course. I hope this is the correct place to post this. (Please excuse any potential english mistake I made trying to translate this).

Problem 1:
Copper (conductor) sphere of radious R with an spheric bubble inside placed at distance c from the center, with radius b. The metalic sphere has charge Q.

1.-Find the electric potential inside the bubble
2.-Is the result modified if the bubble is not a sphere?

Problem 2:

1.-Explain what a monochromatic plane wave is, identify the dirction of propagation, the velocity of propagation, wave lenght and polarization.

2.- In the case of plane electromagnetic waves, probe E and B fields are perpendicular between each other. and perpendicular to the direction of propagation.

Last edited by a moderator: Aug 28, 2015
2. Aug 28, 2015

### Staff: Mentor

Let's try problem #1 - what have your tried so far?

3. Aug 28, 2015

### Rene Manzano

I will try to use this math symbols the best I can (first time using them on a post :) ). I might be wrong, but what I think is that I should have the charge Q distributed in both surfaces so I have the denisty of charge ρ= Q/ (4πR^2+4πb^2). Then I can use Gauss and have the electric field inside the bubble? ρ / ∈0. After that I'm completley lost.