A donkey pulls a cart along a road with constant force of 100N. A constant force of friction of 50 N acts on the cart. The QUESTION: Calculate the mass of the cart if net force accelerated it at a rate of 10m/s^2

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?