Wow...joiemoie wrote: At a certain strain, hooke's law breaks. This is roughly at 100% strain. However, fully elastic bungees have a very low strain and always remain relatively constant. At nationals, strain for the fully elastic bungee can go up to 74%, while partially elastic bungees can go past 500%. It will have deviated from hooke's law a long time ago.
Just realized that this was the wording that I was looking for back when we were having the discussion about partially elastic vs. fully elastic--I just couldn't figure out how to word it (and couldn't remember the word "Strain"
)If you guys do decide to work with a fully elastic cord, one problem that you'll soon come across is that when testing, you stretch the bottom part of the cord much more often than higher parts of the cord, and so the lower part of your cord becomes more elastic than the top (to the point where it deviates from your equation enough to hit the ground). To counter this, find your modulus of elasticity, do ONLY a few trials (under 5) to verify the accuracy, and then you're good. At the competition, do just one more test of your modulus of elasticity right before impound, and use that value for the event.blindmewithscience wrote:1-It wears out slower than cords with a non-elastic portion, as it slows it down over a longer period of time and a longer distance.
