Production of Induced EMF

IMPORTANT

Production of Induced EMF: Overview

This topic covers concepts such as Motional Emf in a Conductor, Fleming's Right Hand Rule for Induced Current, Derivation of Motional Emf, Production of Induced EMF for Time Varying Magnetic Flux, etc.

Important Questions on Production of Induced EMF

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A jet plane is travelling towards wets at a speed of 1800 km h-1. What is the voltage difference developed between the ends of the wing having a span of 25 m, if the Earth’s magnetic field at the location has a magnitude of  5×104 T and the dip angle is 30° ?

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Figure shows a rectangular conductor PQRS in which the conductor PQ is free to move in a uniform magnetic field B perpendicular to the plane of the paper. The field extends from x=0 to x=b and is zero for x>b. Assume that only the arm PQ possesses resistance r. When the arm PQ is pulled outward from x=0 with constant speed v, the joules heating loss from bx<2b would be:

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Derive the expression for alternating EMF when the rectangular coil is rotating in a uniform magnetic field.

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A rectangular frame ABCD made of a uniform metal wire has a straight connection between E and F made of the same wire as shown in the figure. AEFD is a square of side 1 m and EF=FC=0.5 m. The entire circuit is placed in a steadily increasing uniform magnetic field directed into the plane of the paper and normal to it. The rate of change of the magnetic field is 1 T s-1, the resistance per unit length of the wire is 1 Ω m-1.  If the current in segments BE is x22 A, find x.
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What is the concept of flux?

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What does flux mean in physics?

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What is magnetic flux?

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What is flux cutting rule?

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In figure, wires P1Q1 and P2Q2, both are moving towards right with speed 5 cm sec-1 resistance of each wire is 2 Ω. Then current through resistor is a×10-1 mA

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A metal conductor of length 1 m rotates vertically about one of its ends at angular velocity 5 rad s-1. If the horizontal component of earth's magnetic field is  0.2×10-4 T, then the emf (in μV) developed between the ends of the conductor is

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A six-pole generator with fixed field excitation develops an emf of 100 V, when operating at 1500 rpm. At what speed (in rpm) must it rotate to develop an emf of 120 V?

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A conducting rod PQ of length 1 m is moving with a uniform speed 2 ms-1 in a uniform magnetic field of 4 T which is directed into the paper. A capacitor of capacity 10 μF is connected as shown in the figure. Then the charges on the plates of the capacitor are

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A rod of length 1 m is kept inclined at an angle of 60° with the uniform magnetic field of 0.5 T. If the rod is moved with a velocity 10 m s-1. perpendicular to the field, the induced emf is

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A copper rod is moved in a magnetic field. The charge developed across its ends will be proportional to _____.

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A loop ABCD is moving with velocity v towards right. The magnetic field is 2 T. Loop is connected to a resistance of 9 Ω. If steady current of 2 A flows in the loop, then value of v, if loop has resistance of 4 Ω is (given, AD=30 cm )

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A conducting rod of length L=1 m is moving with a uniform speed v=2 m s-1 on conducting rails in a magnetic field B=5 T as shown. On one side, the end of the rails is connected to a capacitor of capacitance C=2 μF. Then the charges on the capacitor plates are:

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A flexible circular loop 20 cm in diameter lies in a magnetic field of magnitude B=1 T , directed into the plane of page as shown. The loop is pulled at the points indicated by the arrows forming a loop of zero area in 0.314 sec. The average emf induced (in mV) in the loop is.

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Whenever a magnet is moved either towards or away from a conducting coil. An emf is induced then the magnitude of induced emf is independent of

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Two parallel rails of a railways track, insulated from each other and with the ground, are connected to a millivoltmeter. The distance between the rails is one metre. A train is travelling with a velocity of 72 km h-1 along the track. The reading of the millivotmeter (in mV) is (Vertical component of the earth's magnetic induction is 2×10-5T),

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A solid metal cube of edge length 2 cm is moving in a positive y -direction at a constant speed of 6 m/s. There is a uniform magnetic field of 0.1 T in the positive z -direction. The potential difference between the two faces of the cube perpendicular to the x -axis, is: