Aball with a mass of 160 g which contains 4.40×108 excess electrons is dropped into a vertical shaft with a height of 115 m . at the bottom of the shaft, the ball suddenly enters a uniform horizontal magnetic field that has a magnitude of 0.200 t and direction from east to west. if air resistance is negligibly small, find the magnitude of the force that this magnetic field exerts on the ball just as it enters the field. use 1.602×10−19 c for the magnitude of the charge on an electron.

Is a  vector quantity  that refers to "the rate at which an object changes its position." imagine a person moving rapidly - one step forward and one step back - always returning to the original starting position. while this might result in a frenzy of activity, it would result in a zero velocity. because the person always returns to the original position, the motion would never result in a change in position. since velocity is defined as the rate at which the position changes, this motion results in zero velocity. if a person in motion wishes to maximize their velocity, then that person must make every effort to maximize the amount that they are displaced from their original position. every step must go into moving that person further from where he or she started. for certain, the person should never change directions and begin to return to the starting position.