Aproton initially traveling at 50,000 m/s is shot through a small hole in the negative plate of a parallal-plate capacitor. the electric field strength inside the capacitor is 1,500 v/m. how far does the proton travel above the negative plate before temporarily coming to rest and reversing course? assume the proton reverses course before striking the positive plate.

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?