What is Motional EMF?

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Motional EMF refers to the voltage generated in a conductor that is moving in a magnetic field. When a conductor moves in a magnetic field, the magnetic flux through the conductor changes, and this changing flux induces an electric field within the conductor, causing a voltage to be generated.

The magnitude of the motional EMF is given by the formula:

EMF = Blv

where B is the magnetic field strength, l is the length of the conductor that is moving, and v is the velocity of the conductor.

Motional EMF is the basis of operation for many electrical devices such as electric generators, which convert mechanical energy into electrical energy, and electric motors, which convert electrical energy into mechanical energy. It is also an important concept in the field of electromagnetism and plays a crucial role in understanding the behavior of electric circuits.

One practical example of motional EMF is the operation of a simple generator. In a generator, a coil of wire is rotated inside a magnetic field, generating an EMF in the coil. This EMF can be used to power electrical devices or to charge batteries.

Motional EMF

Motional EMF

Also read:

Related Concepts
AC Generator	Unit of Magnetic Flux	Faraday Constant
magnetic flux	Eddy Currents	Inductance
Uses of Inductor	Electric Field	induced electromotive force and current

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What is Motional EMF?

CBSE CLASS XII Related Questions

3.
This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

5.
A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a set of readings of the voltmeter and the ammeter by using the rheostat.

Similar Physics Concepts

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What is Motional EMF?

CBSE CLASS XII Related Questions

3.This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

5.A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a set of readings of the voltmeter and the ammeter by using the rheostat.

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

3.
This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

5.
A student sets up the circuit as shown in the figure to find the value of unknown resistance X and records a set of readings of the voltmeter and the ammeter by using the rheostat.