How much work do you do when you lift a child with 50N of force .5m?

The direction of the current in an alternating current circuit remains constant. is direct. changes repeatedly. changes randomly.

Four friends, a, b, c, and d are standing varying distances away from a speaker which is producing sound waves.

The average atmospheric pressure on earth is approximated as a function of altitude by the relation patm = 101.325 (1 − 0.02256z)5.256, where patm is the atmospheric pressure in kpa, and z is the altitude in km with z = 0 at sea level. determine the approximate atmospheric pressures at atlanta (z = 306 m), denver (z = 1610 m), mexico city (z = 2309 m), and the top of mount everest (z = 8848 m).