Why does a change of magnetic flux induce an EMF?

How and why does a changing magnetic flux induce an emf? Why doesn't a static one also produce one? How are the electric and magnetic forces related? Why do you move a wire through a magnetic field so that the wire, the motion, and the magnetic field are all mutually orthogonal in order to produce the emf? I want an intuitive explanation please. Also take into consideration that I'm a high school student.

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Dale
Mentor
2021 Award
This is going to be a very difficult question to answer. “Why” questions are notoriously difficult to answer. Basically, to answer a “why” question requires that the questioner and the answerer have an agreed upon set of accepted assumptions or background that can be used as explanations.

Unfortunately, you exclude math (not intuitive), explanations by contradiction, and any concepts introduced after high school. I have no idea what explanations are left, what common basis of understanding you will allow. Since you have a priori rejected so much of our usual possible common basis, please spend some time explaining what we can use in an acceptable answer.

• DaveE
This is going to be a very difficult question to answer. “Why” questions are notoriously difficult to answer. Basically, to answer a “why” question requires that the questioner and the answerer have an agreed upon set of accepted assumptions or background that can be used as explanations.

Unfortunately, you exclude math (not intuitive), explanations by contradiction, and any concepts introduced after high school. I have no idea what explanations are left, what common basis of understanding you will allow. Since you have a priori rejected so much of our usual possible common basis, please spend some time explaining what we can use in an acceptable answer.
Please explain as simply as you can, if you reference something I don't understand I'll ask for clarification

Dale
Mentor
2021 Award
Please explain as simply as you can, if you reference something I don't understand I'll ask for clarification
If you accept the potential formulation of Maxwell’s equations then Faraday’s law is a vector identity.

If you accept the conservation of magnetic flux then Faraday’s law can be derived using differential forms.

If you accept Coulomb’s law and relativity then Faraday’s law can be derived using tensors.

• etotheipi and berkeman
gmax137
How and why does a changing magnetic flux induce an emf? Why doesn't a static one also produce one?
How's this: with an emf or voltage, you can do work (run a motor, or heat a resistor, etc.), right? If you could do that with a static field, you would be getting something for nothing. You never get something for nothing, so you don't get emf from a static magnetic field.

Dale
Mentor
2021 Award
How's this: with an emf or voltage, you can do work (run a motor, or heat a resistor, etc.), right? If you could do that with a static field, you would be getting something for nothing. You never get something for nothing, so you don't get emf from a static magnetic field.
Earlier he had a priori rejected any “if not then this would happen” explanations, but he appears to have changed his mind. So maybe this will satisfy him now.

DaveE
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