For a standing wave to form in a medium, two waves must

An engineer designs a roller coaster so that a car travels horizontally for 152 ft, then climbs 137 ft at an angle of 34.0° above the horizontal. it then moves 137 ft at an angle of 48.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Which car has the most kinetic energy? a. a car of mass 1000 kg with a speed of 3 m/s b. a car of mass 2000 kg with speed 7 m/s c. a car of mass 1000 kg with speed 7 m/s d. a car of mass 2000 kg with speed 3 m/s

(a) if the pressure in gas is doubled while its volume is held constant, by what factor do (i) vrms and (ii) change? (b) is it possible to boil water at room temperature (20oc) without heating it? explain.