What is the Ratio of y/x for Zero Net Electric Force on a Charge?

[compute_a_nerd]

Hello all. I am kindof stuck on this problem. It asks: The figure below shows three point charges all posotive. If the net electric force on the center charge is zero, what is the value of y/x.
The answers:
a) 4/9
b) $$\sqrt{2/3}$$
c) $$\sqrt{3/2}$$
d) 3/2
e) 9/4

This is my figuring:

$$K\frac{2q}{x^2} - K\frac{3q}{y^2} = 0$$

But how can I get an actual number without a value for q?
Thanks
Chris

 

[dextercioby]

You can divide the whole equation through $\frac{1}{4\pi\epsilon_{0}\epsilon_{r}}=:K$ and "q" and then try to see which numbers fit the equation left...

Daniel.

 

[wais]

Hi Chris,

Thank you for sharing your thoughts on the problem. It seems like you have already set up the correct equation using Coulomb's Law to find the net electric force on the center charge. However, you are correct that without a specific value for the charges, it is not possible to calculate the value of y/x. This is because the value of y/x would depend on the specific values of the charges.

If you have access to the specific values of the charges, you can plug them into the equation you have set up and solve for y/x. Otherwise, you can use the given answer choices and plug them in to see which one satisfies the equation.

I hope this helps. Good luck with solving the problem!