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

Two very large horizontal sheets are 4.25 cm apart and carry equal but opposite uniform surface charge densities of magnitude [tex]\sigma[/tex]. You want to use these sheets to hold stationary in the region between them an oil droplet of mass 364 [tex]\mu[/tex]g that carries an excess of five electrons. Assume that the drop is in vacuum.

2. Relevant equations

E = F_{E}/ q

F_{g}= mg

E = [tex]\sigma[/tex] / 2[tex]\epsilon[/tex]_{0}

[tex]\epsilon[/tex]_{0}= 8.854 * 10^{-12}C^{2}/N*m^{2}

3. The attempt at a solution

I calculated the F_{g}because I know the F_{E}must be equal and opposite of gravity in order to be suspended.

I also calculated the net charge of the oil drop which was 5xe^{-}(the charge of one electron) = 8.01 * 10^{-19}C.

I divided the F_{E}by the net charge of the drop to find the Electric Field in N/C. I then multiplied E (electric field) by 2[tex]\epsilon[/tex]_{0}to solve for [tex]\sigma[/tex] but this is not the correct answer apparently.

Where have I went wrong?

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# Homework Help: Electric Fields of horizontal sheets

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