Advertisements
Advertisements
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.
Advertisements
उत्तर
(i)According to Lenz's law, the polarity of emf induced in the coil always opposes the change in the magnetic flux responsible for production of induced emf.
(ii) Lenz's law is used to determine the direction of current induced in the closed circuit. Let us consider an example to illustrate it. When a north pole of a bar magnet is brought closer to a coil, as shown in figure, the amount of magnetic flux linked with the coil increases. So, the current induced in the coil is directed such that it opposes this change in magnetic flux responsible for production of induced current, which is possible only when the current induced in the coil is in anticlockwise direction of the observer on the side of the magnet.
Similarly, the direction of induced current can be found when north pole of bar magnet is moved away from the coil. As the magnetic flux in this case decreases, the induced current is in the clockwise direction.
\
APPEARS IN
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 direction of induced current in metal rings 1 and 2 when current I in the wire is steadily decreasing?
The battery discussed in the previous question is suddenly disconnected. Is a current induced in the other loop? If yes, when does it start and when does it end? Do the loops attract each other or repel?
Explain, with the help of a suitable example, how we can show that Lenz's law is a consequence of the principle of conservation of energy.
Which of the following statements is not correct?
Energy dissipate in LCR circuit in
Consider a magnet surrounded by a wire with an on/off switch S (Figure). If the switch is thrown from the off position (open circuit) to the on position (closed circuit), will a current flow in the circuit? Explain.
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.
