Electric fields are caused by particles that have charge. Gravitational fields are caused by particles that have mass. What is the property of a particle that causes it to interact with a magnetic field?

I've read that magnetic fields are caused by charged particles that are moving in an electric field. However, since any charged particle in an electric field experiences a force on it which causes it to move, doesn't this mean that an electric field is impossible to detect without a magnetic field also being present, and vice versa? How would a magnetic field and electric field differ in this case?

I've also read that magnetism is caused by groupings of particles with the same spin state. Is this the quantum mechanical explanation, and if so then how do groupings of such particles create a magnetic field?


If all the spins are aligned, then a magnetic field is created. It is the direction of the spin that causes the attraction or repulsion (As far as my understanding goes)

An electric field can be created by a stationary charge (electrostatics). It is only when this charge moves that the magnetic field is created.

  • $\begingroup$ How do bar magnets work then. Is there any moving charge within them? $\endgroup$ – Pancake_Senpai Aug 3 '17 at 10:38
  • 1
    $\begingroup$ Nope, nice and static, just aligned spin! If you get a sheet of paper and draw a load of loops moving in a clockwise direction inside a bar magnet (to model the spins) you should be able to see how them aligning creates a general field $\endgroup$ – G.Bruce Aug 3 '17 at 11:21
  • $\begingroup$ google.co.uk/…: $\endgroup$ – G.Bruce Aug 3 '17 at 11:24
  • $\begingroup$ Or you can do the classic experiment with a bar magnet and a compass - if you're willing to spend the time on that. $\endgroup$ – Jordan Abbott Aug 3 '17 at 11:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.