posted by Jess on .
please check my answers.
17. explain how the sport of pole vaulting dramatically changed when flexible fiberglass poles replaced still wodden poles?
-the fiberglass poles had more momentum and PE than still wooden poles?
20. does the international space station have gravitational pe? ke? explain?
-It has gravitation pe, but I am stuck as to why?
25. what does the work theorem say about the speed of a satillite in circular orbit? (this one I don't understand)
30.a moving hammer hits a nail and drives it into a wall. if the hammer hits the nail with twice the speed, how much deeper will the nail be driven? if it hits with three times the speed?
-would it be three times the speed
no, yes but why, no , no
fiberglass poles can store energy (from horizontal velocity) and transfer it upward.
Gravational PE occurs when two bodies are separated, right?
The satellite in orbit uses no energy.
work = velocity^2
distance is proportional to velocity^2
so what is twice square?