00:02
So in this question actually it is said that there are two concentric loops.
00:06
Consentic loops, one loop is like this and another is also like this.
00:10
So they are having the same center.
00:12
So center is same.
00:13
Now what happens? since the magnetic field at the center is zero, what is magnetic field at the center? magnetic field at the center is zero.
00:20
So what we will do b1 is equal to b2.
00:23
That is magnetic field due to bigger loop is equal to due to lower loop.
00:28
Its magnitude will be equal.
00:30
So mod value of this will be equal.
00:32
Means they will be opposite in sign only because one will be attractive and one will be repulsing.
00:36
That is where the net magnetic field will be 0.
00:39
So how magnetic field in the center of the loop is given as mu not i1 upon 2 r1.
00:45
R1 is the radius of this one.
00:48
Let's say this is r1 and another is r2...