Induced current opposes the change that produced it.
The induced current flows in a direction that opposes the change in flux that caused it. This is conservation of energy: negative sign in Faraday's law. It explains eddy-current braking and back-EMF in motors.
Dropping a magnet through a metal pipe slows it dramatically.
Lenz's law explains the direction of induced currents and is why induced effects act to resist motion, such as in brakes and eddy current sensors.
Induced current opposes the change that produced it.
Lenz's law explains the direction of induced currents and is why induced effects act to resist motion, such as in brakes and eddy current sensors.
It encodes Lenz's law: the induced EMF creates a current whose field opposes the change in flux. Without the sign, energy would not be conserved.
Yes. The back EMF in a motor opposes the supply voltage, which limits the current and sets the operating speed.
Typical applications include explaining the drag from an eddy current brake on a train, understanding why a magnet falls slowly through a copper pipe and predicting the reaction of a motor to a sudden load change.
Study "Faraday's law" first (topic 21 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Opposition to change. Magnet falling through a copper tube slows. Inductors resist current change.
Dropping a magnet through a metal pipe slows it dramatically.
The next topic is "Safety and grounding", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 22 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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