Chapter 20, Problem 28P

To determine

The direction of magnetic field $\overrightarrow{B}$ at each of the points C, D, and E in the plane of the page.

Answer to Problem 28P

The direction of the magnetic field will be in the counter-clockwise direction as shown in Figure 1.

Explanation of Solution

Introduction:

According to the right-hand rule, if thumb indicates the direction of the current flowing, then the curled fingers will direct towards the rotating magnetic field.

Since the current in the wire is out of the plane of the paper. Thus, according to the right-hand rule, the magnetic field will be in the counter-clockwise direction. Now, if a circle is drawn covering all three points C, D, and E. Then, the tangent drawn at these points on that circle will indicate the direction of the magnetic field as shown below.

  

Figure 1

Conclusion:

The direction of the magnetic field will be in the counter-clockwise direction as shown in Figure 1.