Electric/Gravitational Forces

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To find the ratio of the magnitudes of the electrical and gravitational forces between a proton and an electron, use the formulas F_e = k(q)(q')/r^2 for electrical force and F_g = G(m1)(m2)/r^2 for gravitational force. The ratio is calculated by dividing the electrical force by the gravitational force, resulting in k(q)(q') / G(m1)(m2). Use the charge of the electron (1.6e-19 C) and the mass of the proton and electron in the calculations. This straightforward division provides the desired ratio of the forces acting between the two particles.
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Find the ratio of the magnitudes of the electrical and the gravitational forces acting between a proton and an electron separated by an arbitrary distance d.


F= k(q)(q')/r^2 and
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The q's are in an absolute value sign. How do I find the ratio? Is it as simply as dividing it out?
 
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thst1003 said:
The q's are in an absolute value sign. I believe there is an additional equation similar to this one that deals with gravity that I need to use as well but I can't find it.

Although I have a lot of trouble believing that you have not encountered this already, I will just take your post at face value. Here is the equation you seek:

http://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation
 
I changed the question. I have encountered it.
 
that's a trivial problem asked on electrostatics. Yep, you divide it for a ratio.
 
What exactly do you divide? Is it Electrical force/Gravitational force using 1.6e-19 C for the electron and the electron? So it would be k(q)(q) / G(m1)(m2) ?
 
thst1003 said:
What exactly do you divide? Is it Electrical force/Gravitational force using 1.6e-19 C for the electron and the electron? So it would be k(q)(q) / G(m1)(m2) ?

In short: yes. You divide exactly what you were ASKED to divide (emphasis mine below):

thst1003 said:
Find the ratio of the magnitudes of the electrical and the gravitational forces acting between a proton and an electron separated by an arbitrary distance d.
 
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