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bbbbbev
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A disk of radius 1.4 cm has a surface charge density of 4.9 µC/m2 on its upper face. What is the magnitude of the electric field produced by the disk at a point on its central axis at distance z = 12 cm from the disk?
I tried solving this problem in the same way you would solve a similar problem with a ring instead of a disk, using the equation E = ((k)(z)(surface charge density))/r, where r = sqrt(z^2 + R^2). z is the y-component of r, the distance between the charges, and R is the radius, which is the x-component of r. But I just realized that that equation solves for E_x, I think. I don't know how to solve for E because I don't know theta or E_y. Could someone please explain this problem!? I feel like I have no idea what is going on with the situation laid out in the problem. I'm lost. I would really appreciate any kind of help you could give!
Thanks, Bev
I tried solving this problem in the same way you would solve a similar problem with a ring instead of a disk, using the equation E = ((k)(z)(surface charge density))/r, where r = sqrt(z^2 + R^2). z is the y-component of r, the distance between the charges, and R is the radius, which is the x-component of r. But I just realized that that equation solves for E_x, I think. I don't know how to solve for E because I don't know theta or E_y. Could someone please explain this problem!? I feel like I have no idea what is going on with the situation laid out in the problem. I'm lost. I would really appreciate any kind of help you could give!
Thanks, Bev