An object with a mass of 7.8 kg is pulled on a horizontal surface by a horizontal pull of 50 n to the right. the friction force on this object is 30 n to the left. what is the acceleration of the object? 0.16 m/s^2
10 m/s^2
2.6 m/s^2
6.4 m/s^2

According to social exchange theory, altruistic behaviors benefit the individual who performs them.

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?

Suppose a soccer ball is kicked from the ground at an angle 20.0º above the horizontal at 8.00 m/s. the y-velocity is determined to be 2.74 m/s. how long will the ball be in the air? assume the ball lands at the same height at which it was kicked.