Chapter 21, Problem 21P

When a thin 12.0 cm iron rod moves with a constant velocity of 4.50 m/s perpendicular to the rod in the direction shown in Figure 21.56, the induced emf across its ends is measured to be 0.450 V. (a) What is the magnitude of the magnetic field? (b) Which point is at a higher potential, a or b? (c) If the rod is rotated clockwise by 90° in the plane of the paper, but keeps the same velocity, what is the potential difference induced across its ends?

Figure 21.56

Problem 21.