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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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What is an electromagnet? Describe the construction and working of an electromagnet with the help of a labelled diagram.
State whether the following statement are true or false:
A generator works on the principle of electromagnetic induction.
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An induced current is produced when a magnet is moved into a coil. The magnitude of induced current does not depend on:
(a) the speed with which the magnet is moved
(b) the number of turns of the coil
(c) the resistivity of the wire of the coil
(d) the strength of the magnet
Describe one experiment to demonstrate the phenomenon of electromagnetic induction.
In which of the following case does the electromagnetic induction occur?
A magnet is moved through a loop of wire .
Name and state the law which determines the direction of induced current.
or
State Fleming’s right-hand rule.
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Draw a simple labeled diagram of a step-down transformer.
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Name the following diagram and explain the concept behind it.
Draw a labelled diagram to show how an electromagnet is made.
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- State your observation when the current is switched on.
- Give an explanation for your observation in (i).
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- In which position will the coil ultimately come to rest?
- State four ways of increasing the magnitude of force acting on the coil.
The energy stored in a 50 mH inductor carrying a current of 4 A is ______
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Shown in the figure below is a metre bridge set up with null deflection in the galvanometer. The value of the unknown resistance R is ______
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A generator has an e.m.f. of 440 Volt and internal resistance of 4000 hm. Its terminals are connected to a load of 4000 ohm. The voltage across the load is ______.
Name some equipment that uses electromagnetism for functioning.
Induced current flows through a coil ______.
Which of the following phenomena makes use of electromagnetic induction?
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