The maximum energy a bone can absorb without breaking is surprisingly small. For a healthy human of mass 60kg, experimental data show that the leg bones can absorb about 200J (a) From what maximum height could a person jump and land rigidly upright on both feet without breaking his legs? Assume that all energy is absorbed in the leg bones in a rigid landing.(b) People jump from much greater heights than this; explain how this is possible.

To do work, this truck uses energy stored in chemical fuel and an electrical battery. how much total energy does this truck put out?

In positive numbers less than 1, the zeros between the decimal point and non zero are significant

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.