00:01
Hi there, so for this problem, we are told that the wire semicircles that is shown in this figure have already a and b, and we need to calculate the magnitude of the net magnetic field that the current in the wires produce at the point b.
00:18
We need to express your answer in terms of the current, a, the radius a and the radius b, and also the magnetic constant mu -sub -0.
00:30
So with that said, we know that the magnetic field produced by a semi -circular section of wire, as in this case, is just given by musup 0 times the current, and this divided by two times the separation between the point where we are measuring.
01:03
In the magnetic field and the position at which there is the wire.
01:11
So let's call this the radius r.
01:13
And of course, we need to divide this by two because it is a semicircle.
01:18
So in here we'll take that this is musup 0 times the current and it divided by four times the radius.
01:27
Now with that said, the first thing that we need to determine in this case is the direction.
01:33
Of the magnetic fields produced by the small circular sediment and the peak and the bit sediment here.
01:45
Let's call this the big one and this just a small one.
01:55
The direction of the magnetic field is given by the right -hound rule using the direction of the current.
02:04
Now as you can see, the current in the small semicircular reception of wire is counter -clothwise.
02:16
So with that said, the direction is outward...