why is the Right Hand Rule in electromagnetism true?



Here is a description of the right hand rule – https://www.khanacademy.org/test-prep/mcat/physical-processes/magnetism-mcat/a/using-the-right-hand-rule

I understand THAT this is true, and have even directly seen experimental evidence that it is true, but what i cannot wrap my brain around is WHY this is true.

So please internet, why is the field always to the right?

In: Physics

Because it’s defined that way. We could have just as easily built the mathematical structure such that there was a ‘left hand rule’ – all that we’d be doing is reversing some polarities.

It depends on the charge under consideration – positive charges right hand rule, negative charges left hand rule. This all comes about because like charges repel and opposite charges attract.

That it is a right hand rule is arbitrary and depend on what we have defined as positive. The definition of a positive charge and negative charge is arbitrary and it they was swapped you get a left hand rule.

The charge was defined back in the day it in a way. The charge particle was then considered to be positive and move from the negative to positive in a electrical circuit. This is decade before the electrons were discovered. They are the particle that move in a electrical circuit but the opposite way of what is defined as electrical current. If the electron charge was know a lot earlier the likely result is they would be defined as positive and we would use a left hand rule.

The question of why a electrical and magnetic field and charge particles interact that way is perhaps a question that is impossible to answer. Electo-magnetism is one of four fundamental forces in the universe. So the best you can get might just be that is how the universe works.
If there is a lower level explanation the question you just move the problem one step down.

Science do not ask the question “why?” question but “how do it happen?” or “what will happen?” [https://medium.com/the-polymath-project/science-does-not-ask-why-9b80e6c81a9e](https://medium.com/the-polymath-project/science-does-not-ask-why-9b80e6c81a9e) is a good read

it is true by definition. You can rewrite all books of physics using a left-hand rule, and everything will still hold true.

Most physicists know how to sort through all this. Vectors are unaffected by the handness choice. Pseudo-Vectors are affected, they change signs when you switch the handness.

This also means: Pseudovectors are never directly observed (e.g. an axis of rotation). All you can observe is a plane – and you need to apply some handiness rule to assign it to a direction.