Eddy Currents

IMPORTANT

Eddy Currents: Overview

This topic covers concepts, such as Eddy Currents, Direction of Eddy Current, Disadvantages of Eddy Current, Method to Minimize Eddy Currents, Application of Eddy Currents, Magnetic Braking in Trains, Electromagnetic Damping, Induction Furnace, etc.

Important Questions on Eddy Currents

EASY
IMPORTANT

Given below are two statements: one is labelled as
Assertion A and the other is labelled as Reason R
Assertion A: A bar magnet dropped through a metallic cylindrical pipe takes more time to come down compared to a non-magnetic bar with same geometry and mass.
Reason R: For the magnetic bar, Eddy currents are produced in the metallic pipe which oppose the motion of the magnetic bar.
In the light of the above statements, choose the correct answer from the options given below

EASY
IMPORTANT

A bar magnet is released from rest along the axis of a very long vertical copper tube. After some time the magnet will

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Certain galvanometers have a fixed core made of non magnetic metallic material. The function of this metallic material is

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Spherical insulating ball and a spherical metallic ball of same size and mass are dropped from the same height. Choose the correct statement out of the following {Assume negligible air friction}
 

MEDIUM
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Find direction of current in position I and position II in the given diagram:

Question Image

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In transformers, laminated core is used to reduce energy losses due to

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IMPORTANT

Eddy currents developed on a conductor moving in a magnetic field will tend to

MEDIUM
IMPORTANT

A bar magnet of mass m is suspended from the ceiling with a massless string and is set into oscillations. A gold metal plate is brought close to the oscillating pendulum. The oscillations will damp due to induction of eddy currents in the metal. Which one of the following statements is true if the gold plate is replaced by a steel plate having the same physical dimensions. (Of the two, note that gold is a better conductor of electricity.)

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Eddy currents travel in

HARD
IMPORTANT

Electromagnetic damping is inversely proportional to

MEDIUM
IMPORTANT

Electromagnetic damping is similar to

HARD
IMPORTANT

Electromagnetic damping is associated with:

HARD
IMPORTANT

Which of the following is a disadvantage of eddy currents?

HARD
IMPORTANT

The working of an analogue type electric power meter is based on

HARD
IMPORTANT

Which of the following is responsible for the working of an analogue electric power meter?

HARD
IMPORTANT

Which of the following is essential for the working of an induction furnace?

HARD
IMPORTANT

On what principle does an induction furnace works?

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Which of the following phenomena is employed in an induction furnace?

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___________ is not an application of eddy current.

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IMPORTANT

Which of the following does not hold for eddy currents?