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प्रश्न
Why and where are eddy currents are undesirable? How are they minimized?
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उत्तर
Undesirable effects of eddy currents:
The soft iron core is used in dynamo transformers, motors, generators, etc. When a.c is passed through these instruments the flux changes and eddy currents are set up in the core. Therefore, the core is heated up so the electrical energy is wasted in the form of heat energy.
Minimization of the undesirable effect of eddy current:
- To minimize the undesirable effect of eddy currents, laminated or insulated iron core is used which minimizes the magnitude of eddy currents.
- If the surface area of the metal plate is reduced, amount of eddy current generated is reduced.
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संबंधित प्रश्न
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A metallic bob A oscillates through the space between the poles of an electromagnet (See the figure). The oscillations are more quickly damped when the circuit is on, as compared to the case when the circuit is off. Explain.
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(a) hold the sheet there if the metal is magnetic
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The plane in which eddy currents are produced in a conductor is inclined to the plane of the magnetic field at an angle equal to ______.
Identify the wrong statement.
What are eddy currents?
Two simple pendula of length L and 4L are pulled aside to the right and are at rest so that they make an angle 30° with the vertical. They are then released simultaneously at time t = 0. The time after which they will be in phase is ______.
If the length of a simple pendulum increases by 5%, then its period shall increase by ______.
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Eddy currents are also known as ______
A metal plate is getting heated. It can be because ______.
- a direct current is passing through the plate.
- it is placed in a time varying magnetic field.
- it is placed in a space varying magnetic field, but does not vary with time.
- a current (either direct or alternating) is passing through the plate.
