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प्रश्न
Use Lenz’s law to determine the direction of induced current in the situation described by the figure.
A circular loop being deformed into a narrow straight wire.
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उत्तर
According to Lenz’s law, the direction of the induced emf is such that it tends to produce a current that opposes the change in the magnetic flux that produced it.
The area and, by extension, the magnetic flux associated with a deformed circular loop are smaller than those of a straight wire. Consequently, the magnetic field is pointing upwards because an induced current is set up in an anticlockwise manner.
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संबंधित प्रश्न
State Lenz's law. Illustrate, by giving an example, how this law helps in predicting the direction of the current in a loop in the presence of a changing magnetic flux.
Show that Lenz's law is a consequence of conservation of energy.
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(a) The south pole faces the ring and the magnet moves towards it.
(b) The north pole faces the ring and the magnet moves towards it.
(c) The south pole faces the ring and the magnet moves away from it.
(d) The north pole faces the ring and the magnet moves away from it.
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Predict the direction of induced current in the situation described by the following figure.
