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प्रश्न
Show diagrammatically how an alternating emf is generated by a loop of wire rotating in a magnetic field. Write the expression for the instantaneous value of the emf induced in the rotating loop.
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उत्तर
Generation of an alternating e.m.f. by a loop of wire rotating in a magnetic field
Expression of the instantaneous value of the induced e.m.f. in a rotating loop
ε = NBAω sinωt
Where N = number of turns in armature coil
B = Magnetic field vector
A =Area vector of the coil
ω = Angular speed
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संबंधित प्रश्न
A solenoid of length 1.5 m and 4 cm in diameter possesses 10 turns per metre. A current of 5 A is flowing through it. The magnetic induction at a point inside the solenoid along the axis is ............................. .
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- π × 10-5 T
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AB is a coil of copper wire having a large number of turns. The ends of the coil are connected with a galvanometer as shown. When the north pole of a strong bar magnet is moved towards end B of the coil, a deflection is observed in the galvanometer.
- State the reason for using galvanometer in the activity and why does its needle deflects momentarily when magnet is moved towards the coil.
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- State the conclusion that can be drawn from this activity.
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OR
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