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Electromagnetic Induction CONFUSION

So i get that the induced emf in a coil is that rate of change of flux through the coil. But a coil creates a burge field, which will be uniform inside the coil where the magnet would be. So the magnetic flux density will be constant, if the magnet is moved smoothly at the same speed, the induced current would not change and the field would remain uniform and in time t there would be no change in magnetic flux, so how does this work, wouldnt that mean that the emf induced is 0, but that cant be the case, can it?? :confused:

Reply 1

lerjj

The coil hasn't got any fields of any sort if it's just a coil of wire- picture a spring sitting on a worktop, it's not exactly an electromagnet is it.

When a magnet is moved through it, the magnet has a field, which moves with it. This means a magnetic field moves through the coil, and so there is a changing magnetic field (at one moment there's none, next there is some, so a change must have occurred) So you get an emf.