- #1

paulie

- 13

- 0

## Homework Statement

Two positive point charges, A and B are 6m apart. The electric field intensity at point C, midway between the two charges is 5 N/C directed towards B and the potential at the same point is 45V. Find the magnitude of A and the magnitude of B.

## Homework Equations

E = kQ/r

^{2}

## The Attempt at a Solution

From what I visualize it:

(+A)<---3m--->(-C)<---3m--->(+B)

Using E = kQ/r

^{2}where Q=Er

^{2}/k

Q = (5 N/C)(3 m)

^{2}/ (9x10

^{9}Nm

^{2}/C

^{2}) = 5x10

^{-9}C

which is the answer for A and B I suppose? But the answer key tells me that the answer in A is twice the B. How come? I'm quite confuse on how this works.