Metal sphere left by alien civilization

[winterwind]

voltage/charge problem

Homework Statement

Imagine a small metal sphere left by some alien civilization is floating in space. A
probe is launched directly at the sphere in order to study it. When the probe is
1000 m from the sphere, it detects a voltage of 110.0 V; and when it’s at 100.0 m
it records 10.0 V. What, if any, is the charge on the sphere?

Homework Equations

I used V = (kq)/r

The Attempt at a Solution

Solve for q to get q = V(r/k). Plug in the values for each situation, and get q. The thing is, I get different values of q for each set of values. I must be using the wrong equation...but I can't figure which equation to use that relates charge and volts.

Thanks!

 

[winterwind]

help anyone?

 

[winterwind]

BUMP

It's due tomorrow!