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

Part A (which I already got right) A person scuffing her feet on a wool rug on a dry day accumulates a net charge of -72.1 uC. How many excess electrons does this person get?

Part B (Which is what I need help on) Given the static charge buildup in the previous question, what is the magnitude of the force on an electron at a distance 6.03 m from the person?

2. Relevant equations

So i thought that what you would do is simply find how many coulombs are in an electron, which is 1.6E-19 C. Then convert the uC to C and you would get .000072 C or 7.2E-5 C. So i divided the 7.2E-5 by the 1.6E-19 and got 4.5E14 which was the correct answer. But the part I need help with is finding the magnitude of the force. I would think I could just use coulombs law but I am not really sure what my q1 and q2 would be. Would I use 7.2E-5 and the 4.5E14? or would i use something else?

3. The attempt at a solution

I did

F=((8.9E9)(4.5E14)(7.2E-5))/6.03^2 and got an answer of 7.9E18 N. which was wrong. not sure where i went wrong

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# Homework Help: How many electrons

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