A college student decides to try bungee jumping. He attaches an elastic bungee cord to his ankles and jumps off a tall bridge across a river. He ends up barely touching the water before the cord jerks him back up.
Which assumptions are reasonable to make in this problem?
A. The student can be treated as a particle moving with constant speed.
B. The student can be treated as a particle moving with constant acceleration.
C. The student cannot be treated as a particle.
D. The air resistance is substantial.
E. The air resistance is negligible.
F. The amount of heat generated in the bungee cord is substantial.
G. The amount of heat generated in the bungee cord is negligible.
I. The bungee cord applies a constant (or zero) force on the student.
J. The bungee cord can be modeled as a spring that obeys Hooke's law.
And it can be multiple assumptions...thanks for the help as I can't seem to be getting a right answer.
2006-11-22 19:24:15 · 7 answers · asked by Kris 1 in Science & Mathematics ➔ Physics
E, G, J
in this problem, it can be assumed that time of fall is of sec's only hence air resistance can be negligible. problem can be solved using hooke's law though i am not sure what principle bungee rope works. heant generation which will take place in rope will be much smaller then actual work done. There can't be a constant speed or accelaration coz both r changing constantly, for example to start of jump speed is zero, acc downwards, where as at bottom point speed is again zero but acc. is upwards. n in between speed is non zero.
last, u can treat him as a particle for simlification as long as u keep air resistance negligible. u must realize that neeta (coff. of air resistance is very small n play effective role at high speeds).
cord applies different force at different moments becoz of hooke's law.
I hope it helps......
2006-11-22 19:50:49 · answer #1 · answered by Mann 2 · 0⤊ 0⤋
Initial moment - he is ready to jump off - E and K are 0. Final moment G is 0. Actually, G can be considered 0 any where, so it will be more precise to say that G is minimum at final moment and maximum initially. You can argue a "natural 0" for G at the surface of the earth, but that is variable. The phrase "barely touches water" is, I understand, intended to mean "almost the earth's surface". The same can be said (mathematically)about E, but there seems to be a more "natural" 0 for it (unstretched condition).
2016-05-22 21:25:23 · answer #2 · answered by Anonymous · 0⤊ 0⤋
If you need to download Falling Block Game you can get it here for free: http://j.mp/1pnRHY9
it's completely free and it's very fast to install
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Try it out
2014-09-22 01:45:07 · answer #3 · answered by ? 2 · 0⤊ 0⤋
J only
2006-11-22 20:13:45 · answer #4 · answered by whay i lost my ?s 6 · 0⤊ 0⤋
Sounds like a good demo to me!!
The coolest thing MY physics prof had us do was pile students onto a cart for momentum demos.
P.S. C, D, G, I dunno about J.
2006-11-22 19:30:06 · answer #5 · answered by Anonymous · 0⤊ 0⤋
B, E, I,G,J
2006-11-22 19:42:03 · answer #6 · answered by gp4rts 7 · 0⤊ 0⤋
b,e,f,j...
2006-11-22 20:39:01 · answer #7 · answered by go4sambhav 1 · 0⤊ 0⤋