00:01
In the given problem, the conductor is converted into a shape like this.
00:11
First of all, it is bent into a semicircle having a radius of a.
00:21
Then again, it is bent into another semicircle like this, which is having a radius b.
00:33
The current i is passing through this loop in the lower semicircle it is in counterclockwise direction then in the upper semicircle, it will be in a clockwise direction.
00:53
As we know, the expression for magnetic field at the center of a current carrying coil having a single loop is given by mu not i by two r for the whole loop circular loo so for a semicircle a semicircle the magnetic field will be given by half of this magnetic field means mu not i by four r this will be the expression for the magnetic field at the center of a semicircle.
01:38
And the direction of the magnetic field at the center is found using the rule as if the current is in a counterclockwise direction, this phase will start behaving like a north pole.
01:56
And as we know, current comes out of the north pole.
02:00
So here the magnetic field will be coming out of the plane of paper...