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

Two objects are identical and small enough that their sizes can be ignored relative to the distance between them, which is 0.296 m. In a vacuum, each object carries a different charge, and they attract each other with a force of 1.80 N. The objects are brought into contact, so the net charge is shared equally, and then they are returned to their initial positions. Now it is found that the objects repel one another with a force whose magnitude is equal to that of the initial attractive force. What is the initial charge on each object, the answer to part (a) being the one with the greater (and positive) value?

2. Relevant equations

1) q1= 2*[tex]\sqrt{(Fe*r\stackrel{2}{})/k}[/tex] - q2

2) q1*q2= (Fe*r[tex]\stackrel{2}{}[/tex])/k

3. The attempt at a solution

I solved for q2 in the second equation. I ended up with a quadratic equation: (-7.58E4[tex]\stackrel{+}{-}[/tex][tex]\sqrt{7.58E8 - 4*8.99E9*-1.58E-1}[/tex]) / 2*8.99E9

The two solutions are 2.47E-7 C and -8.68E-6 C

By using the first equation to solve for q1, none of those solutions are satisfying since I don't get a negative charge for q1.

Can you tell me what I'm doing wrong

Also I solved for the final charge by taking the square root of q1*q2, in the second equation, and multiplying the result by 2. I got 8.38E-6 C

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# Homework Help: Electric force

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