Assume the bike has a mass of 20 kg and is moving down at -9 m/s when it is thrown off the balcony. When the bike hits the ground it still has a mass of 20 kg but the bike is not longer moving. What is the change in momentum of the bike?

Acave rescue team lifts an injured spelunker directly upward and out of a sinkhole by means of a motor-driven cable. the lift is performed in three stages, each requiring a vertical distance of 11.0 m: (a) the initially stationary spelunker is accelerated to a speed of 4.80 m/s; (b) he is then lifted at the constant speed of 4.80 m/s; (c) finally he is decelerated to zero speed. how much work is done on the 78.0 kg rescue by the force lifting him during each stage

Aweight lifter raises a 1600 n barbell to a height of 2.0 meters. how much work was done? w = fd a) 30 joules b) 3000 joules c) 320 joules d) 3200 joules

Describe how the motion of a spring being pushed forward and backward is similar to the motion of air particles in a sound wave.