# Homework Help: What is the magnitude of the electric field?

1. Jul 9, 2014

### zoomba91210

1. The problem statement, all variables and given/known data
Two charged particles are fixed on the x-axis 11 cm apart. The one on the left has a net charge of +25uc and the one on the right has a net charge of -11uc. What is the magnitude of the electric field 10 cm to the right of the negative charge?

2. Relevant equations
E = (kq)/r^2

3. The attempt at a solution
When I plug in 9.0 x 10^9 for k, 11.0 x 10^-6 C for q and 0.1 m for r, I get the wrong answer.

Thanks for any help!

Last edited: Jul 9, 2014
2. Jul 9, 2014

### TSny

Hello, zoomba91210.

Both charges contribute to the electric field at the point located 10 cm to the right of the negative charge. ("Superposition principle")

Last edited: Jul 9, 2014
3. Jul 11, 2014

### Satvik Pandey

Suppose that a +ve unit test charge is located at a point on which E is to be calculated. Find the net force on that charge due to the two charges.