Avery long ladder 40 feet long, rests against a vertical wall. suppose that the base of the ladder slides away from the wall at a rate of 5 ft/sec. how fast is the top of the ladder sliding down the wall when the bottom of the ladder is 24 feet from the wall? assume that the top of the ladder remains in contact with the wall.

Ten students stand in a circle and are told to make a transverse wave. what best describes the motion of the students? each student bumps the shoulder of his or her neighbor. at the exact time, all students take a step to the right. the students skip clockwise, going in a circular motion. one at a time, each student lifts his or her hands up and then down.

Ateam of astronauts is on a mission to land on and explore a large asteroid. in addition to collecting samples and performing experiments, one of their tasks is to demonstrate the concept of the escape speed by throwing rocks straight up at various initial speeds. with what minimum initial speed vesc will the rocks need to be thrown in order for them never to "fall" back to the asteroid? assume that the asteroid is approximately spherical, with an average density p 3.84 x108 g/m3 and volume v 2.17 x 1012 m3 recall that the universal gravitational constant is g 6.67 x 10-11 n m2/kg2

Ascrew incorporates which other simple machine? lever wheel and axle inclined plane pulley