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shows a deflection on one and the other side. Further, if a steady current is maintained in the coil P and the two coils are moved relative to each other, then also a current is induced in the coil S. Here, it is the flux generated by the current in the coil P that links with the coil S and a change in that flux causes an induced emf in the coil S.
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2. Lenz's Law We have yet not said anything regarding the magnitude and the direction of the inducted emf. This direction of emf and the resultig direction of the induced current can be inferred from the considerations based on the principle of conservation of energy and this leads us to Lenz's law. When a current flows in a coil, magnetic flux is produced due to this current and the coil now acts as a magnet. Which face of the coil acts like a north pole and which face becomes a south pole depends upon the direction of the current in the coil. Fig. 3 shows a cross section of the coil. Looking at the coil if the currentappears to be flowing through, it in a counterclockwise direction, then the side of the coil facing the observer is its north pole. If the current appears Clockwise then the side towards the observer is the south pole. This is made clear in fig. 3.
Consider moving a bar magnet with its north pole towards the coil. When the magnet is moved towards the coil, if the induced current is such that the side of the coil facing the magnet becomes a south pole, then there would be a force of attraction betweer the magnet and the coil, and due to this force magnet would be further drawn nearer. Thus, the induced current would be gen
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