Which of the following descriptions describes electromagnetic induction? A. Current running through a wire creates a magnetic field. B. Moving a conductor through a magnetic field generates a current through the conductor. C. Connecting a conductive wire to both ends of a battery allows current to flow. D. Moving north poles of two magnets away from each other decreases potential energy.

A step-down transformer has a voltage of 400 V through the primary coil and 200 V through the secondary coil. There are 5 loops in the secondary coil. How many loops are in the primary coil? A. 2 loops, C. 10 loops, B.5 loops, D. 20 loops.

During seven complete ac voltage cycles (in the United States) what is the average voltage: (a) 0 V, (b) 60 V, (c) 120 V, or (d) 170 V?

A single conductor moves through a magnetic field and generates a voltage. In what direction should the wire be moved, relative to the magnetic field to generate the minimum voltage?

A magnet is placed on a refrigerator to hold up a calendar. As the magnet approaches the refrigerator, the potential energy between the magnet and the refrigerator decreases. Explain why.