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→About Back emf
===About Back emf===
*Occurs [[Back EMF|Back emf]] occurs due to [[Lenz's Law|Lenz's Law]], which states that the direction of the [[Electromagnetic *Induction|induced]] [[Electromotive Force|emf]] is such that it opposes the change causing it.
*In an [[Motor|electric motor]], back [[Electromotive Force|emf]] increases with the [[speed]] of the [[motor]].
*It limits the current flowing through the motor as the [[speed]] increases.
*[[Back EMF|Back emf]] is crucial for the functioning of devices like [[motor]]s and [[Electrical Transformer|transformers]] by preventing excessive currents.
*It is a key factor in the design and operation of [[Alternating Current|AC]] and [[D.C. Motor|DC motors]].
===Examples===
*When an [[Motor|electric motor]] starts, the [[Back EMF|back emf]] is initially zero, allowing maximum [[Electrical Current|current]].
*[[Back EMF|Back emf]] in [[Electrical Transformer|transformers]] helps regulate the [[Electrical Current|current]] and [[Potential Difference|voltage]] during operation.