Question

So I'm trying to calculate some mechanics for an electrostatic attraction/repulsion system and I want to make sure that I'm using the correct numbers. I did a bunch of research on my own and I think I have it right, but I'm hoping that someone more experienced can help make sure that I am using the correct formulas.

As far as I understand coulombs law states that the force will be:

F = ( K * Q1 * Q2) / r²
where:

F = the attractive or repulsive force
K = 8.98 x 10⁹
Q1 = the charge on the first plate
Q2 = the charge on the second plate
r = the distance separating the plates in meters
Is this correct? Is it different when it's plates and not points charges, or does it sum to the same thing either way?

Answer 1

Yes, your understanding of Coulomb's law is correct. The electrostatic force between charged plates can be calculated using the formula F = (K * Q1 * Q2) / r².

Step-by-step explanation:

Yes, your understanding of Coulomb's law is correct. The formula to calculate the attraction or repulsion force between two charged plates is F = (K * Q1 * Q2) / r². Here, F represents the force, K is Coulomb's constant (8.98 x 10^9 Nm²/C²), Q1 and Q2 are the charges on the plates, and r is the distance separating the plates in meters.

The formula remains the same whether you are dealing with point charges or charged plates. However, for plates, the charges involve surface area, while for point charges, the charges are concentrated at a single point. The result is the same as long as the surface area of the plates is small compared to the distance between them.