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

Charge 1 is 8nC and is located at x=-1m. Charge 2 is 12nC and is located at x=3m. Find x where e field is equal to 0 due to the 2 charges.

2. Relevant equations

e=kq/(r^2)

3. The attempt at a solution

The answer is x=1.8, but I just can't seem to get anywhere near that. I know that x has to be between -1m and 3m b/c the E-field due to the 2 charges can only cancel out when x is in between.

E1=e field due to charge 1

E2=e field due to charge 2

0=E1-E2 <<<it's minus because E2 is acting in the negative directive

0=kq1/(x+1)^2 - kq2/(3-x)^2

0=8/(x+1)^2 - 12/(3-x)^2 <<canceled out k and 10^-9 from the nano.

8/(x+1)^2 = 12/(3-x)^2 << the answer is 1.8, I don't want to write out the rest so just plug 1.8 in. When you plug it in it doesn't equal each other.

From that my answer isn't even close to 1.8m. I think I messed up somewhere in the denominator of the equation above, but I can't see how.

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# Homework Help: Find where e-field is 0 question.

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