What is the difference between reflection and refraction

Oxygen and hydrogen gas are at the same temperature t.what is the ratio of kinetic energies of oxygen molecule and hydrogen molecule if oxygen is 16 times heavier than hydrogen.

An electric clothes dryer has a resistance of 8 ohms. it draws 30 a of current. what is the voltage, in volts, of the wall outlet that it is plugged into?

Ablue car pulls away from a red stop-light just after it has turned green with a constant acceleration of 0.5 m/s 2 . a green car arrives at the position of the stop-light 6.5 s after the light had turned green. if t = 0 when the light turns green, at what time does the green car catch the blue car if the green car maintains the slowest constant speed necessary to catch up to the blue car? answer in units of s.