For her 83th birthday, my mother decided to try skydiving (good for her!). She is about 5 ft 4 in tall, and about 140 lbs. In her excitement, she jumped out of the plane with her purse still in hand. Of course, she promptly let go of the purse moments after she jumped. The purse, in turn, released a tube of lipstick and a tennis ball. I don’t know why she had a tennis ball in her purse. Using your knowledge of aerodynamic drag and terminal velocity, estimate answers to the following questions.
You will need to make reasonable assumptions about the shape and weights of the various items involved, and possibly the orientation of the falling objects. Assume constant density and temperature for the atmosphere.
1) What body position should she assume in order to achieve the lowest terminal velocity? What is that terminal velocity?
2) What body position should she assume in order to achieve the highest terminal velocity? What is that terminal velocity?
3) Beginner skydivers typically open their parachutes at no less than 4000 ft. At what altitude should my mother jump from the plane in order to ensure that she is able to reach the terminal velocity while she is still above 4000 ft in (1) and (2) above?
4)In what order will the objects (lipstick, tennis ball, and purse) strike the ground?
5) At 4000 ft when mom opens the parachute, is she below or above the released objects (lipstick, tennis ball, and purse)?
6) Suggest a reasonable method for one to measure my mother’s velocity. This could either be done by an observer on the ground or by asking her to carry some sort of sensor.