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प्रश्न
Which of the following scientist invented the rule of electromagnetic induction?
पर्याय
Newton
Kepler
Mendeleev
Michael Faraday
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उत्तर
Michael Faraday
संबंधित प्रश्न
A metal rod `1/sqrtpi `m long rotates about one of its ends perpendicular to a plane whose magnetic induction is 4 x 10-3 T. Calculate the number of revolutions made by the rod per second if the e.m.f. induced between the ends of the rod is 16 mV.
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State the factors on which the strength of an electromagnet depends. How does it depend on these factors?
Name and state the law which determines the direction of induced current.
or
State Fleming’s right-hand rule.
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Can a transformer work when it is connected to a D.C. source? Give a reason.
Draw a simple labeled diagram of a step-down transformer.
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Answer the following:
State the principles of the electric motor and electric generator.
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State the condition at which we say the two coils kept close to each other are perfectly coupled with each other.
Fleming's left hand rule : electric current : : Fleming's right hand rule : _______
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Write the two names in the following diagram.
Fleming’s right hand rule.
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A closely wound circular coil of radius 0.02 m is placed perpendicular to the magnetic field. When the magnetic field is changed from 8000 T to 2000 T in 6 s, an emf of 44 V is induced in it. Calculate the number of turns in the coil.
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A conductor of length 50 cm carrying a current of 5 A is placed perpendicular to a magnetic field of induction 2×10 -3T. Find the force on the conductor.
The working of a dynamo is based on the principle of
A current I = 10 sin(100π t) A is passed in first coil, which induces a maximum e.m.f of 5π volt in second coil. The mutual inductance between the coils is ______.
A sheet is placed on horizontal surface in front of a strong magnetic pole. A force is needed to:
- hold the sheet there if it is magnetic.
- hold the sheet there if it is non-magnetic.
- move the sheet away from the pole with uniform velocity if it is conducting.
- move the sheet away from the pole with uniform velocity if it is both, non-conducting and nonpolar.
Choose the correct statement(s) from the options given below:
Which scientists established in the early nineteenth century that electricity and magnetism are related?
What is a changing magnetic field?
Which charging technology works on electromagnetic induction?
