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प्रश्न
Use Lenz’s law to determine the direction of induced current in the situation described by the figure:
A wire of irregular shape turning into a circular shape.
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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.
A greater area and, by extension, a stronger magnetic flux, are the results of a change in shape. In order to create opposing flux, Lenz's law is used to build up an induced current in the circular wire in an anticlockwise direction. Thus, the upward-directed magnetic field is a result of it.
संबंधित प्रश्न
Describe a simple experiment (or activity) to show that the polarity of emf induced in a coil is always such that it tends to produce a current which opposes the change of magnetic flux that produces it.
Show that Lenz's law is a consequence of conservation of energy.
Predict the directions of induced currents in metal rings 1 and 2 lying in the same plane where current I in the wire is increasing steadily.
Predict the direction of induced current in a metal ring when the ring is moved towards a straight conductor with constant speed v. The conductor is carrying current I in the direction shown in the figure.
Predict the direction of induced current in metal rings 1 and 2 when current I in the wire is steadily decreasing?
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A bar magnet is dropped through a copper ring acceleration of magnet is
Lenz's law gives ______
Same as problem 4 except the coil A is made to rotate about a vertical axis (figure). No current flows in B if A is at rest. The current in coil A, when the current in B (at t = 0) is counterclockwise and the coil A is as shown at this instant, t = 0, is ______.
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A coil is suspended in a uniform magnetic field, with the plane of the coil parallel to the magnetic lines of force. When a current is passed through the coil it starts oscillating: It is very difficult to stop. But if an aluminium plate is placed near to the coil, it stops. This is due to:
Predict the direction of induced current in the situation described by the following figure.
Predict the direction of induced current in the situation described by the following figure.
Predict the direction of induced current in the situation described by the following figure.
