Current passes through a coil shown from left to right. In which direc

1.	Current passes through a coil shown from left to right. In which direction is the induced emf. if the current is (a) increasing with time (b) decreasing in time?
Answer» From Lent’s law, the induced emf must oppose the diange in the magnetic flux. (a) When the current mcreases to the right, so is the magnetic flux. To oppose the increasing flux to the tight. the induced emi Is to the left. i.e.. the point A is at a positive potential relative to point B. (b) When the current to the right is decreasing the induced emf acts to boost up the flux to the right and points to the tight, so that the point A is at a negative potential relative to point B.

Current passes through a coil shown from left to right. In which direction is the induced emf. if the current is (a) increasing with time (b) decreasing in time?

Answer»

From Lent’s law, the induced emf must oppose the diange in the magnetic flux.

(a) When the current mcreases to the right, so is the magnetic flux. To oppose the increasing flux to the tight. the induced emi Is to the left. i.e.. the point A is at a positive potential relative to point B.

(b) When the current to the right is decreasing the induced emf acts to boost up the flux to the right and points to the tight, so that the point A is at a negative potential relative to point B.

Discussion

No Comment Found

Related InterviewSolutions

A current through a coil of self inductance 10 mH increases from 0 to 1 A in 0.1 s. What is the induced emf in the coil?(A) 0.1 V (B) 1 V (C) 10 V (D) 0.01 V
A toroidal coil has an inductance of 47 mH. Find the maximum self-induced emf in the coil when the current in it is reversed from 15 A to -15 A in 0.01 s.
A bar magnet moves vertically down, approaching a circular conducting loop in the xy plane. The direction of the induced current in the loop (looking down the z-axis) is(A) anticlockwise (B) clockwise (C) alternating (D) along negative z-axis.
A flexible wire of irregular shape, abcd, as shown in the figure, turns into a circular shape w,hen placed in a region of magnetic field which is directed normal to the plane of the loop away from the reader. Predict the direction of the induced current in the wire.
While sitting a lawn, Ashok and his friends saw that a bird was sitting on high voltage wire. They observed that when a current passed through the wire, the bird sitting on it flew away. People along with both of them gave their opinions and reasons for it, but nobody was able to give a proper balanced option, but in the last Ashok explained the reason behind it. (a) What are the value displayed by Ashok ?(b) Why as soon as the current passed through a high voltage wire, the bird sitting on it flew away ?
The electric current flowing in a wire in the direction from B to A is decreasing. Find out the direction of the induced current in the metallic loop kept above the wire as shown.
Isabella used an induction stove and explains to her neighbour that due to shortage of LPG one must utilize other sources that are available to produce heat energy; being a Physics teacher Isabella, explains that the oil companies are trying their best to meet the demands for LPG and that as a good citizen one must use other sources wherever feasible. Isabella uses an induction stove having a value of 7 H inductor and the flow of current from 10 A to 7 A in x 10-2 seconds. (i) In the above, what is the quality, you find in the Physics teacher ?(ii) Calculate the emf generated in the above ?
Predict the polarity of the plate A of the capacitor, when a magnet is moved towards it, as shown in the figure.
Predict the directions of induced current in metal rings 1 and 2 lying in the same plane where current I in the wire is increasing continuously.
While checking with metal detector at the airport, Imran was asked to take out the material from his pant and shirt pockets. Imran got annoyed and argued with airport security asking the reasons for such procedure. He was conveyed that as per security rule, the passengers and their luggage will be checked for security check to ensure safe travel. (i) What is the value that imparts us in the above scenario ? (ii) Briefly explain the working principle of a metal detector