Question

1. An aluminum ring of radius 5.00 cm and resistance 3.00 × 10–4 O is placed on top of a long air-core solenoid with 1 000 turns per meter and radius 3.00 cm, as shown in the sketch below. Over the area of the end of the solenoid, assume that the axial component of the field produced by the solenoid is half as strong as at the center of the solenoid. Assume the solenoid produces negligible field outside its cross-sectional area. The current in the solenoid is increasing at a rate of 270 A/s. (a) What is the induced current in the ring? At the center of the ring, what are (b) the magnitude and (c) the direction of the magnetic field produced by the induced current in the ring?

2. The square loop in the sketch shown below is made of wires with total series resistance 10.0 O. It is placed in a uniform 0.100-T magnetic field directed perpendicularly into the plane of the paper. The loop, which is hinged at each corner, is pulled as shown until the separation between points A and B is 3.00 m. If this process takes 0.100 s, what is the average current generated in the loop? What is the direction of the current?

3. In the sketch shown below, the bar magnet is moved toward the loop. Is Va – Vb positive, negative, or zero? Explain.

Answer 1