A long solenoid with 15 turns per cm has a small loop of area (2.0 cm^{2}) placed inside the solenoid normal to its axis. If the current carried by the solenoid changes steadily from 2.0 A to 4.0 A in 0.1 s, what is the induced emf in the loop while the current is changing?

Predict the direction of induced current in the situation described by the following Fig. 6.15(a).

Predict the direction of induced current in the situation described by the following Fig. 6.15(f).

Use Lenz’s law to determine the direction of induced current in the situations described by Fig. 6.16: A wire of irregular shape turning into a circular shape;

Predict the direction of induced current in the situation described by the following Fig. 6.15(e).

Predict the direction of induced current in the situation described by the following Fig. 6.15(d).

A horizontal straight wire 10 m long extending from east to west is falling with a speed of (5.0 m s^{-1}), at right angles to the horizontal component of the earth’s magnetic field, (0.30 \times 10^{-4} Wb m^{-2}). What is the direction of the emf?

A horizontal straight wire 10 m long extending from east to west is falling with a speed of (5.0 m s^{-1}), at right angles to the horizontal component of the earth’s magnetic field, (0.30 \times 10^{-4} Wb m^{-2}). Which end of the wire is at the higher electrical potential?

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  Emf is __________
  
  

Use Lenz’s law to determine the direction of induced current in the situations described by Fig. 6.16: A circular loop being deformed into a narrow straight wire.

A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field of magnitude 0.3 T directed normal to the loop. What is the emf developed across the cut if the velocity of the loop is (1 cm s^{-1}) in a direction normal to the shorter side of the loop? For how long does the induced voltage last in each case?

Current in a circuit falls from 5.0 A to 0.0 A in 0.1 s. If an average emf of 200 V induced, give an estimate of the self-inductance of the circuit.

Predict the direction of induced current in the situation described by the following Fig. 6.15(c).

In a salient pole synchronous motor, the developed reluctance torque attains the maximum value when the load angle in electrical degrees is

A pair of adjacent coils has a mutual inductance of 1.5 H. If the current in one coil changes from 0 to 20 A in 0.5 s, what is the change of flux linkage with the other coil?

Predict the direction of induced current in the situation described by the following Fig. 6.15(b).

A 1.0 m long metallic rod is rotated with an angular frequency of (400 rad s^{-1}) about an axis normal to the rod passing through its one end. The other end of the rod is in contact with a circular metallic ring. A constant and uniform magnetic field of 0.5 T parallel to the axis exists everywhere. Calculate the emf developed between the centre and the ring.