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1. Is the magnitude of the induced emf across a circuit directly proportional to or equal to the rate of change of magnetic flux linkage? Or are both definitions the same?
2. (Original post by Yellowmellow)
Is the magnitude of the induced emf across a circuit directly proportional to or equal to the rate of change of magnetic flux linkage? Or are both definitions the same?
Induced emf = - N x d(Phi)/dt = - rate of change in magnetic flux linkage.

It equals it.

The magnitude of the induced emf simply means you ignore direction and hence the negative sign, so |emf| = N x d(Phi)/dt.
3. The constant of proportionality is precisely 1, so they're the same.
4. in the equation, its equal.

When answer in word, like if the question ask you why increasing the magnetic flux linkage increases the induced EMF? then you can say because emf is proportional to the magnetic flux linkage, there when Nd(Phi) increases, emf increases. and emf is inversely proportional to change in time
5. Its only equal if you measure emf in volts and Magnetic flux in Webers.

col's rules of EM induction questions.

Any Q that asks about size of emf or why there is an emf, write out faraday's law
Any Q that asks about direction of emf, write out lenz's law.

Always

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