Coulomb's law, R is the inverse to F?

AI Thread Summary
Coulomb's law describes the relationship between the force (F) between two charged objects and the distance (R) separating them, where force is inversely proportional to the square of the distance (F ∝ 1/R^2). To graph this relationship, R is treated as a variable, and the force can be plotted against R using known values for the charges and the constant k. For example, with charges Q1 and Q2, the equation can be expressed as F = k * (Q1 * Q2) / R^2. As R increases, the force decreases, illustrating the inverse relationship. Understanding this concept allows for accurate representation of the force-distance relationship in a graph.
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This isn't homework, just a bit of extra study that is annoying me. Can't really seem to get my head around this bit.

If you have a worked equation of Coulomb's law and all known variables; Force, Distance between two objects and the charge in Coulomb's, how do you represent this in a graph? I've read that you do the inverse of R^2 which for me is 0.15 metres. I understand that as R increases, the Force decreases and as Force increases, R decreases. How do you represent this on a graph? I don't exactly know how to mathematically represent this as an equation.

Okay so let me give you an example of what I have.

F= 3.4425x10^-5
R= 0.2 so R^2 = 0.04
Q1 = 17x10^-9
Q2 = 9x10^-9

The R is the initial distance though, how do I calculate the distance it has moved due to the force being applied? F=MA?

Need to set the graph up like this by the way, but obviously with numbers.

http://www.aplusphysics.com/courses/regents/electricity/images/InverseSquareLaw.png
 
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As far as graphing, you need to recognize that F is a function of r, F(r). So you treat r as you would any variable and graph it with the values for k and q given: http://www.wolframalpha.com/input/?i=Plot%5B%28%28%288.988%C3%9710^9%29%2817*10^-9%29%289*10^-9%29%29%2F%28r^2%29%29%2C{r%2C0%2C25}%5D
 
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