How does change in current induce electromotive force

AI Thread Summary
Inductance is the property of an electrical circuit where a change in current induces an electromotive force (EMF) that opposes the change, as explained by Lenz's Law. When current flows through a circuit, it generates a magnetic field, and any alteration in this current alters the magnetic field, leading to the induction of an opposing EMF, commonly referred to as "back-EMF." The right-hand grip rule can be used to visualize the relationship between current direction and magnetic field orientation. Understanding these concepts is crucial for grasping how circuits respond to changes in current. The discussion emphasizes the fundamental principles of electromagnetism in electrical circuits.
jeff1evesque
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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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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.
 


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?
 


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.
 
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