How do we surely know that electric force is 1/r²? If it is just because “it works” then why can’t it be 1/r^(2.0000001) or something, how do we know?

Question

Edit 1:
I was assuming the correctness of maxwells equations, how flux remains same in the absence of additional charge. So is it to say that that is 100% correct or just simple it can be a really really good approximation and we dont know?

Edit 2:
The best explanation I got till now: We simply do not know if it is really 1/r^2, but experimentally we have found that this model is very accurate to several decimal points(2.0000…). The 1/r^2 and maxwells equations are same, they are correct or wrong together. And in my opinion, the divergence equation for electric field seems very simple, and we found its high accuracy through experiments, so I have a feeling that it must all be exact 1/r^2. But still, I don’t think we have a way to find out because the equations are themselves the starting point which describes the experiments very well, we don’t have derivation for them and I don’t think we will ever have, and on the other hand, our only way to check is by experiments which won’t give 100% confidence accuracy.

Edit 3:
Another perception is about unit-dimentions. Like ( c^2 ) * e0*u0 = 1, which binds the units of e0 and u0, so electric and magnetic formulas must together be right or wrong. I can’t think or anything more right now, but there can be some other unit-dimension constraints that I am missing which will complete the picture.

In: 40

Answer 1

The short answer is we did the math.
A lot of concepts in physics rely on the 1/r^2 law, gravity, electromagnetic, acoustics and optics.

The idea is this, if you have a square in front of you 1 unit away with 1 unit sides. The square has an area of 1 square units. Now move the square to be 2 units away from you. Now, the sides of the square look like they became half as small, .5 units. Making the “area” of the square appear to be .25 units squared, or 1/r^2 = 1/4.

So as objects get further away from each other, the “area” seen by each object decreases with 1/r^2. The official derivation for the physics equations can be done by using the conservation of energy and calculus. 🙂