A 47.4 kg student runs down the sidewalk and jumps w/ a horizontal speed of 4.2 m/s onto a stationary skateboard. The student and skateboard move down the sidewalk w/ a speed of 3.95 m/s. What is the mass of the skateboard?

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?

Astone is thrown into a pond. what happens to the amplitude of the resulting waves as they get farther from the point where the stone hit the water? explain.

Wavelength,frequency,and energy are related.what happens to a wave as it’s wavelength gets shorter?