When would the velocity of a wave traveling in a medium change?

A - only if a property of the wave changes

B - only if a property of the medium changes

C - if a property of both the wave and the medium changes

D - never

What is the kinetic energy of a 74.0 kg skydiver falling at a terminal velocity of 52.0m/s?

Protons are made up of ___ up quark (s) and ___ down quark (s). a. 1, 1 b. 1, 2 c. 2, 1 d. 2, 2

A 60-kg woman stands on the very end of a uniform board, which is supported one-quarter of the way from one end and is balanced. What is the mass of the board? a. 60 kg b. 30 kg c. 20 kg d. 15 kg e. 120 kg

Which phrases describe organisms that formed index fossils

Talia loves to jump rope. she jumps 879 times in 403 seconds. at what speed is she jumping.

Which wave characteristic has the unit hertz

A stretched spring has 5184 J of elastic potential energy and a spring constant of 16,200 N/m. What is the displacement of the spring?

A block of mass 1.3 kg is resting at the base of a frictionless ramp. A bullet of mass 50 g is traveling parallel to the ramp surface at 250 m/s. It collides with the block, enters it, and exits the other side at 100 m/s.

Metals are good thermal conductors - that is, when there is a temperature difference across their ends, they transfer energy very efficiently from the higher temperature end to the lower temperature end.

Some stars are so far away that their light hasn't reached Earth yet. A million years in the future, will the sources of light we see when we look up at night be the same? Why or Why not?