# Finding Electric Field for Three Point Charges

1. Sep 19, 2011

### cheerspens

1. The problem statement, all variables and given/known data
The questions are based off of the diagram I attached.
First, I had to find the strength of the electric field due to each charge at (0 cm, 8 cm).
Now I need to find the total electric field (both magnitude and direction) at (0 cm, 8 cm) and the total electric potential due to these three charges at the origin (0 cm, 0 cm) and (0 cm, 8 cm).

2. Relevant equations
E=$\frac{KeQ}{r^2}$
V=$\frac{KeQ}{r}$
Ue=qVTOT

3. The attempt at a solution
I found the electric fields to be:
E1= 2742295.52
E2= 2742295.52
E3= 8.33333.33

Now how do I go from here to the total electric field and then total electric potential?

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2. Sep 20, 2011

### ehild

Remember that the electric field is a vector quantity. Find the direction of the field vectors due to each charge at point (0,8) and add them as vectors.

ehild