Amans walks 200 meter on 20 seconds. what is the man speed?

speed=distance traveled/ time

a. 2 m/s
b. 5 m/s
c. 10 m/s
d. 100 m/s

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

How does the kinetic energy of a charge change as the charge moves under the effect of an electric field from higher potential to lower potential? a.the kinetic energy increases.b.the kinetic energy decreases.c.the kinetic energy remains the same.d.the kinetic energy is always zero.

Amoving electron has kinetic energy k1. after a net amount of work w has been done on it, the electron is moving one-quarter as fast in the opposite direction. (a) find w in terms of k1. (b) does your answer depend on the final direction of the electron's motion?