Here is an experiment on jumping up you can do.
(a) Crouch down and jump straight up, as high as you can. Estimate the location of your center of mass, and measure its
height at three stages in this process: in the crouch, at lift-off, and at the top of the jump. Report your measurements.
You may need to have a friend help you make the measurements.
(b) Analyze this process as fully as possible, using all the theoretical tools now available to you, especially the concepts
in this chapter. Include a calculation of the average force of the floor on your feet, the change in your internal energy,
and the approximate time of contact from the beginning of the jump to lift-off. Be sure to explain clearly what
approximations and simplifying assumptions you made in modeling the process.