# Electrostatic force question

1. Feb 25, 2015

### LanaArwen

First off idk if this is the right topic to post in but I've been at this problem for hours and I have no idea how to solve it.

Three metal spheres are situated in positions forming and equlateral triangle with sides of 0.012 m. X has a charge of -2.5 C. Y has a charge of 3.00 C. Z has a charge of 4 C. Calculate the electrostatic force on the Y charge.

I have tried calculating Fxy and Fzy and adding those values together but i get the wrong answer. I also have no idea of the angle

2. Feb 25, 2015

### SteamKing

Staff Emeritus
What don't you understand about equilateral triangles?

Since you know the location of each charge relative to one another, the electrostatic force between them should be treated like a vector: magnitude and direction.

3. Feb 25, 2015

### BvU

Hello Lana, welcome to PF
Cold you post your work ? we might be able to see where it goes wrong -- if at all (book answers aren't always the right answers!)

4. Feb 25, 2015

### haruspex

For future reference, this belongs in Introductory Physics, not Advanced.