A 30 gram ball rolls along a flat surface at a constant speed in the same direction over 4 meters in 20 seconds. Which is the speed of the ball? (speed = distance = time)
A. 0.2 meters per second
OB. 0.5 meters per second
c. 20 meters per second
D. 80 meters per second

Please answer this FAST!

Abucket full of water weights 4 kg and water well is 10m deep. a girl draws water from the well. it takes the girl 3 minutes to draw a bucket full of water from the well. what is the power of the girl?

While standing outdoors one evening, you are exposed to the following four types of electromagnetic radiation: yellow light from a sodium street lamp, radio waves from an am radio station, radio waves from an fm radio station, and microwaves from an antenna of a communications system. rank these type of waves in terms of increasing photon energy.

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?