Two loudspeakers are about 10 m apart in the front of a large classroom. if either speaker plays a pure tone at a single frequency of 400 hz, the loudness seems pretty even as you wander around the room, and gradually decreases in volume as you move farther from the speaker. if both speakers then play the same tone together, what do you hear as you wander around the room?

Ametal ring 4.20 cm in diameter is placed between the north and south poles of large magnets with the plane of its area perpendicular to the magnetic field. these magnets produce an initial uniform field of 1.12 t between them but are gradually pulled apart, causing this field to remain uniform but decrease steadily at 0.240 t/s . (a) what is the magnitude of the electric field induced in the ring? (b) in which direction (clockwise or counterclockwise) does the current flow as viewed by someone on the south pole of the magnet?