What equation for induced EMF?

Thread starter Mariah
Start date Mar 30, 2018
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Emf Induced Induced current Induced emf Magnetism

In summary, the induced EMF equation (EMF = -N * ΔΦ/Δt) is derived from Faraday's law and is used to calculate the induced electromotive force in a conductor. The negative sign represents the direction of the induced current, which follows Lenz's law. However, the equation cannot be used to calculate the magnitude of the current, as the resistance of the circuit must also be taken into account. The induced EMF equation is applicable in any situation where there is a changing magnetic flux through a conductor.

Mar 30, 2018

Mariah

I understand the direction compnent of this question. But I don't understand where the magnitude of the induced current came from? I'm assuming faradays law wasn't used as there wasn't a change in magnetic field?

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Mar 30, 2018

kuruman

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Look up "motional emf".

1. What is the equation for induced EMF?

The equation for induced EMF is given by: EMF = -N * ΔΦ/Δt, where EMF is the induced electromotive force, N is the number of turns in the coil, and ΔΦ/Δt is the rate of change of the magnetic flux through the coil.

2. How is the induced EMF equation derived?

The induced EMF equation is derived from Faraday's law of electromagnetic induction, which states that the induced EMF is directly proportional to the rate of change of the magnetic flux through a conductor. This is expressed mathematically as EMF = -N * ΔΦ/Δt.

3. What does the negative sign in the induced EMF equation represent?

The negative sign in the induced EMF equation indicates the direction of the induced current. It follows Lenz's law, which states that the induced current will flow in a direction that opposes the change in the magnetic flux that caused it.

4. Can the induced EMF equation be used to calculate the magnitude of the induced current?

No, the induced EMF equation only gives the magnitude of the induced electromotive force. To calculate the magnitude of the induced current, the resistance of the circuit must also be taken into account using Ohm's law (I = V/R).

5. In what situations is the induced EMF equation applicable?

The induced EMF equation is applicable in any situation where there is a changing magnetic flux through a conductor. This includes scenarios such as a moving magnet near a coil, a changing current in a nearby wire, or a changing magnetic field through a conductor.