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प्रश्न
In which of the following devices, the eddy current is not used ______
विकल्प
Electromagnet
Induction furnace
Electric heater
Magnetic breaking in train
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उत्तर
In which of the following devices, the eddy current is not used Electric heater.
संबंधित प्रश्न
State any two causes of energy loss in actual transformers.
Two spherical bobs, one metallic and the other of glass, of the same size are allowed to fall freely from the same height above the ground. Which of the two would reach earlier and why?
Describe briefly three main useful application of eddy currents ?
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A metal sheet is placed in front of a strong magnetic pole. A force is needed to ______________ .
(a) hold the sheet there if the metal is magnetic
(b) hold the sheet there if the metal is nonmagnetic
(c) move the sheet away from the pole with uniform velocity if the metal is magnetic
(d) move the sheet away from the pole with uniform velocity if the metal is nonmagnetic.
Neglect any effect of paramagnetism, diamagnetism and gravity.
How are eddy currents generated in a conductor which is subjected to a magnetic field?
Write two examples of their useful applications .
How can the disadvantages of eddy currents be minimized?
Why and where are eddy currents are undesirable? How are they minimized?
Identify the wrong statement.
What are eddy currents?
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If the length of a simple pendulum increases by 5%, then its period shall increase by ______.
Which one is not an application of eddy current?
Consider a metallic pipe with an inner radius of 1 cm. If a cylindrical bar magnet of radius 0.8 cm is dropped through the pipe, it takes more time to come down than it takes for a similar unmagnetised cylindrical iron bar dropped through the metallic pipe. Explain.
