An infinite nonconducting sheet of charge, oriented perpendicular to the x-axis, passes through x = 0. It has area density s1 = -3 µC/m2. A thick, infinite conducting slab, also oriented perpendicular to the x-axis, occupies the region between x = a and x = b, where a = 3 cm and b = 4 cm. The conducting slab has a net charge per unit area of s2 = 4 µC/m2.(adsbygoogle = window.adsbygoogle || []).push({});

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(b) Calculate the surface charge densities on the left-hand (sa) and right-hand (sb) faces of the conducting slab.You may also find it useful to note the relationship between sa and sb.

sa=?

sb=?

where s stands for sigma

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Ok, so I need to figure out the two indivudal surface charges, that will give me the net overall surface charge density.

I know that E=sigma/ (2*epislon)

where E = electric field

epislon= 8.85e-12

I can figure out the electric field values between the two slabs, and the electric fields to the right of the conducting slab.

Total Electric field for slab 1 = sigma_1/(2*epsilon) = -1.69E5 N/C =E_left

Total Electric field from slab 2 is sigam_2/(2*epsilon) = 2.25E5 N/C = E_right

now, I tried setting up this equation

for the left side of slab 2

-E_right+E_left=(sigma_1+sigma_2)/(2*epsilon)

now to the right side of slab 2

E_right+E_left=(sigma_1+sigma_2)/(2*epsilon)

so its a system of equations..but when I solve for one sigma, it totally cancels itself out when plugged into the other equation..I've been at this stupid problem for almost an hour and half..how do I finish this ?

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# Homework Help: Infinite sheet of chargejust need help on sigma stuff

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