a soap bubble is essentially a thin film of water surrounded by air. the colors you see in soap bubbles are produced by interference.

Arotating space station is said to create “artificial gravity”—a loosely-defined term used for an acceleration that would be crudely similar to gravity. the outer wall of the rotating space station would become a floor for the astronauts, and centripetal acceleration supplied by the floor would allow astronauts to exercise and maintain muscle and bone strength more naturally than in non-rotating space environments. if the space station is 200 m in diameter, what angular velocity would produce an “artificial gravity” of 9.80 m/s^{2} 2 at the rim?

Work = force × a. work b. energy c. distance d. momentum

What is the measure of a change in an objects velocity?