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

Determine the magnitude of the electric field at a point midway between a -8.1μC and a 8.9μC charge 8.0cm apart. Assume no other charges are nearby.

Determine the direction.

(Answer in two sig figs.)

2. Relevant equations

E=k/r^2(Q1+Q2)

3. The attempt at a solution

I drew this: -8.1---------p----------8.9

This is what I think I'm supposed to do.

The field due to -8.1 charge points toward it.

The field due to 8.9 points away. So they are both pointing towards the negative charge?

so E=k/.08^2(8.1e-6+8.9e-6)=2.4e7 N/C but this is incorrect. Please explain why! Thanks.

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# Homework Help: Finding the magnitude of an electric field.

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