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प्रश्न
Electromagnetic induction means ______.
विकल्प
Charging of an electric conductor.
Production of magnetic field due to a current flowing through a coil.
Generation of a current in a coil due to relative motion between the coil and the magnet.
Motion of the coil around the axle in an electric motor.
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उत्तर
Electromagnetic induction means generation of a current in a coil due to relative motion between the coil and the magnet.
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संबंधित प्रश्न
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When a bar magnet is pushed towards (or away) from the coil connected to a galvanometer, the pointer in the galvanometer deflects. Identify the phenomenon causing this deflection and write the factors on which the amount and direction of the deflection depends. State the laws describing this phenomenon.
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A) `(qR)/(Bm)`
B)`(qm)/(Br)`
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(a) north pole
(b) east pole
(c) south pole
(d) west pole
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(a) soft iron
(b) brass
(c) aluminium
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A generator works on the principle of electromagnetic induction.
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A loop of wire is held near a magnet.
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(a) What according to you are the values displayed by Puja and her father?
(b) State the phenomenon of light involved in the formation of coloured soap bubbles.
The coil of a moving-coil galvanometer keeps on oscillating for a long time if it is deflected and released. If the ends of the coil are connected together, the oscillation stops at once. Explain.
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The switches in figure (a) and (b) are closed at t = 0 and reopened after a long time at t = t0.
(a) The charge on C just after t = 0 is εC.
(b) The charge on C long after t = 0 is εC.
(c) The current in L just before t = t0 is ε/R.
(d) The current in L long after t = t0 is ε/R.
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D.C. motor ______.
A transformer has 400 turns in the primary winding and 10 turns in the secondary winding. The primary e.m.f. is 250 V and the primary current is 2.0 A. calculate:
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- State your observation when the current is switched on.
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Ansari Sir was demonstrating an experiment in his class with the setup as shown in the figure below.
A magnet is attached to a spring. The magnet can go in and out of the stationary coil. He lifted the Magnet and released it to make it oscillate through the coil.
Based on your understanding of the phenomenon, answer the following question.
Consider the situation where the Magnet goes in and out of the coil. State two changes which could be made to increase the deflection in the galvanometer.
Name some equipment that uses electromagnetism for functioning.
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