A 2.1 ✕ 103-kg car starts from rest at the top of a 5.5-m-long driveway that is inclined at 21° with the horizontal. If an average friction force of 4.0 ✕ 103 N impedes the motion, find the speed of the car at the bottom of the driveway.

Ahot-air balloonist, rising vertically with a constant speed of 5.00 m/s releases a sandbag at the instant the balloon is 40.0 m above the ground. after it is released, the sandbag encounters no appreciable air drag. compute the velocity of the sandbag at 0.250 s after its release.

At the negative terminal of the battery the electron has electric potential energy. what happens to this energy as the electron jumps from the negative to the positive terminal?

Anonzero net force acts on a particle and does work. which one of the following statements is true? the kinetic energy of the particle changes, but the speed of the particle does not change. the kinetic energy of the particle does not change, but the speed of the particle does change. the kinetic energy of the particle changes, but the velocity of the particle does not change. the kinetic energy and the speed of the particle change, but the velocity of the particle does not change. the kinetic energy, speed, and velocity of the particle change.