(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Two small metallic spheres, each of mass 0.2g are suspendedas pednulums by light strings from a common point. The spheres are given the same eletric charge, and it is found that they come to equilibrim when each stringis at an angle of 5degrees with the vertical. If each string is 30 cm long, what is the magnitude of the charge on each sphere?

2. Relevant equations

F=kq1q2/r^2

3. The attempt at a solution

I figured I would need the distance between the spheres so I used x=.3m sin5 deg and multiplied x by 2 to get the distance (r) between them.

Do I add two force equations and put them equal to zero? What other equations do I need? If I try solving for q that way everything cancels out.

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# Homework Help: Problem with Coulomb's Law

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