How Do You Calculate Equilibrium Position Between Charges Using Coulomb's Law?

[charliexx09]

Coloumbs Law & Charges. Please help! :(

Homework Statement

A charge of +2.0 nC and a charge of +8.0 nC are separated by 36.0 cm. Find the equilibrium position for a −2.0 nC charge as a distance from the first charge. Answer in units of cm

Homework Equations

q/r^2

The Attempt at a Solution

I really have no idea how to even start. We just started learning about charged in physics and our teacher hasn't taught us a whole lot (yet we still have to do this homework by ourselves). I just need to understand how to do these problems, and any help would be more than appreciated. Thank you so much and I apologize for not having more information to give!

 

[tiny-tim]

hi charliexx09!

A charge of +2.0 nC and a charge of +8.0 nC are separated by 36.0 cm. Find the equilibrium position for a −2.0 nC charge as a distance from the first charge. Answer in units of cm
…
q/r^2

call the distance from the first charge "x"

use your formula to find the strength and direction of the forces from each charge

then for what value of x are those two forces equal and opposite? ​