How does change in current induce electromotive force

In summary, inductance is the property in an electrical circuit where a change in current induces an electromotive force (EMF) that opposes the change in current. This is known as Lenz's Law and can be seen through the right-hand grip rule, where the induced EMF will be in opposition to the current flow.
  • #1
jeff1evesque
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Statement:
Reviewing the definition of inductance, I found the following definition from Wikipedia:
Inductance is the property in an electrical circuit where a change in the current flowing through that circuit induces an electromotive force (EMF) that opposes the change in current.

Question
Can someone explain to me how change in current will induce an electromotive force (one that will oppose the present current)? And what is meant by a magnetic field is inductive?Thanks,JL
 
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  • #2


Are you familiar with Lenz's Law? A current in a circuit will produce a magnetic field, so when current is changed, magnetic field is changed, and a changing magnetic field will induce an EMF that opposes the change. If I'm not mistaken, this is what people refer to as "back-EMF" in circuits.
 
  • #3


queenofbabes said:
Are you familiar with Lenz's Law? A current in a circuit will produce a magnetic field, so when current is changed, magnetic field is changed, and a changing magnetic field will induce an EMF that opposes the change. If I'm not mistaken, this is what people refer to as "back-EMF" in circuits.

Is there a picture or video I can see of this, so I can see the direction of the EMF in relation to the magnetic field?
 
  • #4


See the right-hand grip rule which relates current direction through a conductor to magnetic field orientation. Induced EMF will be in opposition to the current flow.
 

FAQ: How does change in current induce electromotive force

What is electromotive force (EMF)?

Electromotive force, also known as voltage, is a measure of the electric potential difference between two points in an electrical circuit. It is responsible for the flow of electric current through a conductor.

How does a change in current induce EMF?

According to Faraday's law of induction, a change in current in a conductor will create a changing magnetic field around the conductor. This changing magnetic field will then induce an EMF in any nearby conductor, causing a flow of current.

What factors affect the strength of the induced EMF?

The strength of the induced EMF depends on the rate of change of the current, the number of turns in the conductor, and the strength of the magnetic field.

How is induced EMF used in generators?

In generators, a coil of wire is rotated within a magnetic field, causing a change in current and inducing an EMF. This EMF is then converted into electrical energy, which can be used to power lights, appliances, etc.

Can EMF be induced without a change in current?

Yes, EMF can also be induced by a change in magnetic field or by motion of a conductor through a magnetic field. This is known as motional EMF and is used in devices such as electric motors and generators.

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