What is the difference between an induced emf and a back emf?

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Induced emf and back emf are distinct concepts in electromagnetism. Induced emf occurs when a coil is exposed to a changing magnetic field, generating a potential difference across its ends. In contrast, back emf arises in a coil connected to a power source when the current increases, creating a variable magnetic field that opposes the applied voltage. Both phenomena involve electromagnetic induction but serve different roles in electrical circuits. Understanding these differences is crucial for grasping the principles of electromotive force in various applications.
jayjay112
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What is the difference between an induced emf and a back emf?

(i) i thought they were the same thing? . . .. .
 
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If an open coil is subjected to a variable magnetic field, at the ends of the coil a potential difference is induced which is called induced emf.
If a coil is connected to an emf source and switched on, the rising current will produced an variable magnetic field which in turn produces an emf. It is called back emf.
 
rl.bhat said:
If an open coil is subjected to a variable magnetic field, at the ends of the coil a potential difference is induced which is called induced emf.
If a coil is connected to an emf source and switched on, the rising current will produced an variable magnetic field which in turn produces an emf. It is called back emf.

Thank you for clearing that up!
 
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