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Tom McCurdy
Apr17-05, 08:24 PM
A charge per unit lenth \delta is distributed uniformly along a straight-line segment of length L.

a.) Determine the potential (chosen to be zero at infinity) at point P a distance y from one end of the charged segment and in line with it.

b.) Use the result of a. to compute the compoente of the electric field at P in the y direction

c.) Determine the componet of the electric field at P in a direction perpendicular ro the straight line.

here is the problem with image (http://www.quantumninja.com/hw/scan.jpg)

If anyone could help me with the set up or get started that would be very helpful.

quasar987
Apr17-05, 09:16 PM
It is very frustrating that he has called 'y' this distance that is precisely located on the y axis! It is necessary to rename it. We'll call it 'a'.

When the reference point is taken as infinity, you have probably seen in class that the potential can be found by computing the integral

V(P) = \int \frac{\lambda}{r}dl

"over" the charged body. Where r is the distance from each point of the body to P.

Your goal in evaluating such an integral is to express r and dl as a function of a single variable. Think about it for a while and come back if you haven't found how to do it.

HINT: Try to express r and dl as a function of y. That way you'll take the integral bounds to be 0 and L.