Which event took place during the Copernican revolution, when most people started to believe in a heliocentric model of the solar system? A. Aristotle developed his model of the solar system.
B. Copernicus rediscovered Aristarchus’s heliocentric model.
C. laws of planetary motion.
D. Newton’s theories of gravity were dismissed and considered invalid.

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?