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induced emfs are heat explain using which law?

induced emfs are heat explain using which law?

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Answers (3)

1 month ago
The minus sign in Faraday's law of induction is very important. The minus means that the EMF creates a current I and magnetic field B that oppose the change in flux Δthis is known as Lenz' law. ... The current induced in the coil creates another field, in the opposite direction of the bar magnet's to oppose the increase.
mizta smart
1 month ago
Faraday's law tells us that a changing
magnetic flux will induce an emf in a
coil. The induced emf for a coil with N
loops is: Picture two coils next to each
other, end to end. ... The induced emf is
proportional to the change in
flux,which is proportional to the
change in current in the first coil.
1 month ago
Electromagnetic induction is an incredibly
useful phenomenon with a wide variety of
applications. Induction is used in power
generation and power transmission, and it's
worth taking a look at how that's done.
There are other effects with some
interesting applications to consider, too,
such as eddy currents.
Eddy currents
An eddy current is a swirling current set up
in a conductor in response to a changing
magnetic field. By Lenz¹s law, the current
swirls in such a way as to create a magnetic
field opposing the change; to do this in a
conductor, electrons swirl in a plane
perpendicular to the magnetic field.
Because of the tendency of eddy currents to
oppose, eddy currents cause energy to be
lost. More accurately, eddy currents
transform more useful forms of energy,
such as kinetic energy, into heat, which is
generally much less useful. In many
applications the loss of useful energy is not
particularly desirable, but there are some
practical applications. One is in the brakes of
some trains. During braking, the metal
wheels are exposed to a magnetic field from
an electromagnet, generating eddy currents
in the wheels. The magnetic interaction
between the applied field and the eddy
currents acts to slow the wheels down. The
faster the wheels are spinning, the stronger
the effect, meaning that as the train slows
the braking force is reduced, producing a
smooth stopping motion.
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