Both the laws of e.m.i. can be combined into a single mathematical statement.

and, if the conductor is a coil having N turns, we have:

This is often known as Neumann’s Law.

In the case of a straight conductor moving at 90° to a uniform field, we found

If the conductor moves a distance Ds in time Dt, then the speed, v, is given by v = Ds/Dt.

Therefore, the induced emf is given by

So, in this case, the two statements are equivalent.

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