A point charge q1 = -7.5 μC is located at the center of a thick conducting shell of inner radius a = 2.9 cm and outer radius b = 4.9 cm, The conducting shell has a net charge of q2 = 2.3 μC. (see attachment)(adsbygoogle = window.adsbygoogle || []).push({});

1. What is Ex(P), the value of the x-component of the electric field at point P, located a distance 7.5 cm along the x-axis from q1?

2. What is Ey(R), the value of the y-component of the electric field at point R, located a distance 1.45 cm along the y-axis from q1?

3. What is σb, the surface charge density at the outer edge of the shell? C/m2

4. What is σa, the surface charge density at the inner edge of the shell? C/m2

Ok so I am not very familier with the gauss law and how I set up the equations and such.

Lets just start with number 1.

I know I have to use the law: E= Q/ (4 *pi*eo *r)

where Q is the charge of q1 and r=.029m. I just dont know how the net charge q2 and its radius plays a role into the equation (i know it does but i just dont understand where to plug that in). is Q the difference of q1 and q2? how about r?

Number 3- Surface charge density is E*eo.

So to find this out, I just use E= Q/ (4 *pi*eo *r) where Q=q1 and r=.029 andeo is 8.85*10^-12

Any help would be great. THANKS!

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# Homework Help: Gausses Law

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