Why does change in magnetic flux with time through a coil induce an emf across it? Please explain what happens to the charges in the coil when magnetic flux changes?
Also, why does a constant magnetic flux not induce an emf?
[Physics] Why Does Change of Magnetic Flux Induce an emf
electricityelectromagnetic-inductionelectromagnetism
Best Answer
If you move a wire through a magnetic field so that the wire, the motion, and the magnetic field are all mutually orthogonal, them there is a magnetic force on the charges (because of the motion) that has a component in the direction of the wire (because we arranged the directions the right way). The energy comes from the agent moving the wire, but there is a real force.
When electric and magnetic forces were considered separate, it was merely an experimentally observed fact that if you changed the magnetic field in time there would be a force driving the charges through a wire. But if you look at that magnetic force above, but consider the situation in the frame of the moving wire, there is no magnetic force in that frame, but there is still a force.
You can consider that to be the real reason that changing magnetic fields induce electric fields.