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

You want to create an electric field = < 0, 3x10^4,0 > N/C at location < 0, 0, 0>.

Where would you place a proton to produce this field at the origin?

2. Relevant equations

1/4?? * q/r^2 = 3x10^4 N/C

(if you can't see the 1/4th part of the equation it's 1/(4(pi)(epsilon-not)) == 9.0x10^9 or just k)

3. The attempt at a solution

I moved everything over so that I can solve for r^2 and got this as my equation:

r = sqrt((9.0x10^9)(1.6x10^-19)/(3x10^4))

I ended up getting 2.19x10^-7 however its' saying it's not correct. I have it set up as a vector:

<0, 2.19x10^-7, 0>

Does it need to be negative for a proton in relation to the electric field?

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# Homework Help: Electric fields of particles

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