Asked by raghs321 | 27th Feb, 2010, 06:21: PM

Expert Answer:

Dear student,

Let us say connect a coil of wire to a galvanometer, which is just a very sensitive device we can use to measure current in the coil. There is no battery or power supply, so no current should flow. Now bring a magnet close to the coil. You should notice two things:

  1. If the magnet is held stationary near, or even inside, the coil, no current will flow through the coil.


  2. If the magnet is moved, the galvanometer needle will deflect, showing that current is flowing through the coil. When the magnet is moved one way (say, into the coil), the needle deflects one way; when the magnet is moved the other way (say, out of the coil), the needle deflects the other way. Not only can a moving magnet cause a current to flow in the coil, the direction of the current depends on how the magnet is moved.

a constant magnetic field does nothing to the coil, while a changing field causes a current to flow.

Hope this helps.


Answered by  | 27th Feb, 2010, 09:08: PM

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