I'm getting pretty frustrated with this equation, and I'm not sure what I'm really doing. I've gone to the teacher for help, but as soon as I left school and came home, I've drawn a blank about what he told me..(adsbygoogle = window.adsbygoogle || []).push({});

"At a point in Earth's atmosphere, the electric field is 150 N/C downward and the gravitational field is 9.80 N/kg downward.

a) Determine the electric force on a proton (p^{+}) placed at this point.

b) Determine the gravitational force on the proton at this point. The proton has a mass of 1.67 x 10^{-27}kg."

For a), I'm pretty sure you use the formula:

E = F, and then manipulate it to find F_{e}/q_{e}, right?

I tried doing this:

F_{e}= q * E

F_{e}= 9.80 N/kg * 150 N/C

I get F_{e}= 1470 N, when in the back of the text book it says I should get 2.40 x 10^{-17}N

So I'm not getting the answer that it says in the text book. I was wondering if I did something wrong with 'q', because isn't that the charge, which should be in coulombs? Am I supposed to use the gravitational field and the mass of the proton to find the charge?

I also tried this:

F_{e}= (1.67 x 10^{-27}* 9.80 N/kg) * 150 N/C

and I got F_{e}= 2.50 x 10^{-24}N

Still the wrong answer.

Maybe I'm entering it wrong into my calculator?

As for b), I was told to use:

g = F, then manipulate it to this:_{g}/m

F_{g}= mg

F_{g}= 1.67 x 10^{-27}* 9.80 N/kg

F_{g}= 1.64 x 10^{-26}N

which is right, so I don't really know why I typed this all down! Haha

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# Homework Help: Electric and Gravitational Forces & Fields

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