The superheroine Xanaxa, with a mass of 67.9 kg, is in a hair–raising chase after the 71.7 kg archvillain Lexlax. She leaps from the ground to the top of a 163 m high building, then dives off and comes to rest at the bottom of a 15.9 m deep excavation, where she finds Lexlax and neutralizes him. Does all this bring about a net gain or a net loss of gravitational potential energy? loss gain What is the value of the net gain or net loss? Answer with a positive number. Assume g = 9.8 m/s 2 . net change in potential energy: J

In what direction does the medium move relative to the direction of the wave? explain.

Any color picture tube and electric field exerts a net force of magnitude 1.68x 10^-13 n on an electron the rest mass of an electron is 9.11 x 10^-13 what is the electron acceleration?

Askydiver weighing 140 lb (including equipment) falls vertically downward from an altitude of 19,000 ft and opens the parachute after 18 s of free fall. assume that the force of air resistance, which is directed opposite to the velocity, is of magnitude 0.55|v| when the parachute is closed and is of magnitude 14|v| when the parachute is open, where the velocity v is measured in ft/s. assume that acceleration due to gravity has magnitude 32 ft/s/s; remember that weight is the product of mass and gravitational acceleration. (a) find the speed of the skydiver when the parachute opens. (b) find the distance fallen before the parachute opens. (c) what is the limiting velocity vl after the parachute opens? (d) determine how long the sky diver is in the air after the parachute opens. (e) plot the graph of velocity versus time from the beginning of the fall until the skydiver reaches the ground.