- #1
one_raven
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If you'll allow me to disregard the effects of Strong Interaction, how would I calculate the Electromagnetic Force between two oppositely charged point particles that are in contact with one another?
Let's assume two particles with opposite Elementary Charges: 1.60218E-19 and -1.60218E-19 and start with an assumption of a distance of 1fm...
(Please forgive my pathetic excuse for scientific notation)
F = q1*q2 / (4πεo * r²)
That gives us: 1.60218E * -1.60218E / (1.11265E-10*1E-15^2) = -231
This means, if I understand it correctly, separating the particles from this distance would require 231 Newtons of force. Right?
First: As distance approaches zero, force approaches infinity, but it can never be zero in this equation.
If I'm not mistaken, the distance should be measured from center of mass to center of mass, so it never could be truly zero for massive particles. Given that, my assumption is that the distance for two identical spheres should be the radius.
I get that, but where it loses me is when people say that point particles have no shape, because they exist as a point - therefore have no "size".
I have also read an estimation of the radius of an electron to be about .0689fm.
Do electrons have a physical size, and that's why the distance could never be zero?
Second: If we're talking about two particles touching, shouldn't the Vacuum Permittivity (Dielectric Constant - or whatever term you want to use) be discarded?
If so, how would we do that? What would the resulting equation look like?
If not, why not?
Thanks
Let's assume two particles with opposite Elementary Charges: 1.60218E-19 and -1.60218E-19 and start with an assumption of a distance of 1fm...
(Please forgive my pathetic excuse for scientific notation)
F = q1*q2 / (4πεo * r²)
That gives us: 1.60218E * -1.60218E / (1.11265E-10*1E-15^2) = -231
This means, if I understand it correctly, separating the particles from this distance would require 231 Newtons of force. Right?
First: As distance approaches zero, force approaches infinity, but it can never be zero in this equation.
If I'm not mistaken, the distance should be measured from center of mass to center of mass, so it never could be truly zero for massive particles. Given that, my assumption is that the distance for two identical spheres should be the radius.
I get that, but where it loses me is when people say that point particles have no shape, because they exist as a point - therefore have no "size".
I have also read an estimation of the radius of an electron to be about .0689fm.
Do electrons have a physical size, and that's why the distance could never be zero?
Second: If we're talking about two particles touching, shouldn't the Vacuum Permittivity (Dielectric Constant - or whatever term you want to use) be discarded?
If so, how would we do that? What would the resulting equation look like?
If not, why not?
Thanks