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View Full Version : Nonuniform line of charge, find the electric potential


lu6cifer
Oct31-09, 10:25 AM
A nonuniform linear charge distribution given by λ = bx, where b is a constant, is located along an x axis from x = 0 to x = 0.50 m. Suppose that b = 25 nC/m2 and V = 0 at infinity.


(b) What is the electric potential at the point y = 0.30 m on the y axis?



E = kq/r^2
V = -Ed


Since there's no charge on the y, I think I would have to find the E-field at that point on y, and then use V = -Ed. But how do I integrate the E-field if it's nonuniform?

And is this what I'm supposed to do?

rl.bhat
Oct31-09, 12:01 PM
Potential at any point is given by
V = k*Q/r.
Since charge distribution is nonuniform
V = Intg[k*dq/r] between x = 0 to x = 0.5 m
Now dQ = bx*dx and r = sqrt( 0.3^2 + x^2)
Find the integration.