A bar magnet is falling with some acceleration 'a' along the vertical axis of a long cylindrical coil as shown in the figure. What will be the acceleration of the magnet (whether a > g, a < g or a = g) if (a) coils end are not connected to each other (b) coil ends are connected with each other.
Answers
here is your answer
when condition (a)
there would be no movement of bar magnet,it will keep falling until it touches ground.
when condition( b)
Let the magnet be dropped with its north pole downward. We can consider long tube to be made of many circular loops joined together. At an instant t=0t=0, the force mg acts on the magnet. mmis its mass. As it moves, by Lenz's law, each circular loop in the tube opposes its downward motion and hence upward force will act on it by many such loops. A time will come when the magnet experiences zero net force. Even eddy currents are produced in the magnet. The net force is F−mgF−mg where at some instant will be nil, i.e. F=mgF=mg as I already stated. Even if it has constant velocity at this instant magnetic flux by it linked with those coils is still varied and hence upward force still acts. Hence after this F−mg<0F−mg<0, and magnet accelerated upwards. Now again by Lenz' law coils oppose upward motion of magnet and this process continues till then again it move down.. and so on it just keep on oscillating...
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plz Mark brainliest
when condition (a)
there would be no movement of bar magnet,it will keep falling until it touches ground.
when condition( b)
Let the magnet be dropped with its north pole downward. We can consider long tube to be made of many circular loops joined together.
At an instant t=0t=0, the force mg acts on the magnet. mmis its mass. As it moves, by Lenz's law, each circular loop in the tube opposes its downward motion and hence upward force will act on it by many such loops.
A time will come when the magnet experiences zero net force. Even eddy currents are produced in the magnet. The net force is F−mgF−mg where at some instant will be nil, i.e.
F=mgF=mg as I already stated.
Even if it has constant velocity at this instant magnetic flux by it linked with those coils is still varied and hence upward force still acts.
Hence after this F−mg<0F−mg<0, and magnet accelerated upwards. Now again by Lenz' law coils oppose upward motion of magnet and this process continues till then again it move down.. and so on it just keep on oscillating