Does a tree falling over in a forest make a sound if there is no receptor (human or animal ear) to hear it? In your answer, describe why you think it does or does not. Describe how you would test your hypothesis. Use relevant terms.

If a clock aboard a space ship traveling at 0.900 c of the speed of light relative to earth chimes once at the beginning of the hour and again when it reads one hour later, how much time would an observer on earth say elapsed between the two chimes?

Global warming will produce rising sea levels partly due to melting ice caps but also due to the expansion of water as average ocean temperatures rise. to get some idea of the size of this effect, calculate the change in length (in m) of a column of water 1.45 km high for a temperature increase of 1.12°c. assume the column is not free to expand sideways. as a model of the ocean, that is a reasonable approximation, as only parts of the ocean very close to

In the united states, tornadoes generally occur because of the freezing of ocean water underwater earthquakes meeting of cool and warm air masses shifting of warm and cool ocean currents