# Electric Charge Question

• Jun 1st 2008, 04:20 PM
Jeavus
Electric Charge Question
Neutral metal sphere A, of mass 0.10 kg, hangs from an insulating wire 2.0 m long. An identical metal sphere B, with charge -q, is brought into contact with sphere A. The spheres repel and settle as shown. Calculate the initial Charge on B.

Coulomb's Law Formula = kq1q2/r^2

http://img504.imageshack.us/img504/109/diagram4ty5.png

How do I go about solving this problem? (the book gives 3.9x10^-6C) as the answer)
• Jun 1st 2008, 06:13 PM
topsquark
Quote:

Originally Posted by Jeavus
Neutral metal sphere A, of mass 0.10 kg, hangs from an insulating wire 2.0 m long. An identical metal sphere B, with charge -q, is brought into contact with sphere A. The spheres repel and settle as shown. Calculate the initial Charge on B.

Coulomb's Law Formula = kq1q2/r^2

http://img504.imageshack.us/img504/109/diagram4ty5.png

How do I go about solving this problem? (the book gives 3.9x10^-6C) as the answer)

I'm curious to see a solution for this, as the only way I can think to do it is by method of images, which I would have thought to be too advanced for High School.

-Dan