Question:
The expression for the induced emf contains a negative sign $\left( \xi=-\frac{d\phi}{dt}\right)$. The significance of the negative sign is given by the statement
The expression for the induced emf contains a negative sign $\left( \xi=-\frac{d\phi}{dt}\right)$. The significance of the negative sign is given by the statement
Updated On: Jul 7, 2022
- The induced emf is produced only when the magnetic flux decreases
- The induced emf opposes the changes in the magnetic flux
- The induced emf is opposite to the direction of the flux
- none of the above
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The Correct Option is D
Solution and Explanation
Induced e.m.f. opposes the cause producing it.
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Concepts Used:
Electromagnetic Induction
Electromagnetic Induction is a current produced by the voltage production due to a changing magnetic field. This happens in one of the two conditions:-
- When we place the conductor in a changing magnetic field.
- When the conductor constantly moves in a stationary field.
Formula:
The electromagnetic induction is mathematically represented as:-
e=N × d∅.dt
Where
- e = induced voltage
- N = number of turns in the coil
- Φ = Magnetic flux (This is the amount of magnetic field present on the surface)
- t = time
Applications of Electromagnetic Induction
- Electromagnetic induction in AC generator
- Electrical Transformers
- Magnetic Flow Meter