00:01
Hi, in the given problem, two friends are performing experiment in the physics lab and they claim that in general something has to move in order to induce a current in a coil that has no batteries.
00:19
So suppose here this is the coil wound over a soft iron core.
00:33
This is the coil and there is a galvanometer attached with it.
00:42
This is the needle of this galvanometer which detects the presence of current in this coil.
00:49
Now there is a magnet as the friends are claiming something has to move.
00:58
So that's something first of all in the first experiment which we want to perform.
01:04
This something is a bar magnet.
01:09
And as this bar magnet is having the magnetic field lines coming out of its north pole, so as we will move this magnet close to the coil or away from the coil in both of the cases, the magnetic flux linked with the coil will change and this changing magnetic flux will give rise to the current induced in this coil.
01:36
Means this experiment justifies that we have to move something and that something is magnet in order to create an electric current in this coil.
01:53
Now, in other way, if we want to reject this experiment, now, in other way, if we want to reject this experiment, now in place of this bar magnet, suppose we are having a simple iron rod and we move it close to the same coil or away from this coil...