alright guys I've been going at this problem for a while I can't seem to figure it out. Here it is(adsbygoogle = window.adsbygoogle || []).push({});

A flea is able to jump straight up about 0.40 m. It has been said that if a flea were as big as a human, it would be able to jump over a 100 story building! When an animal jumps, it converts work done in contracting muscles into gravitational potential energy (with some steps in between). The maximum force exerted by a muscle is proportional to its cross-sectional area, and the work done by the muscle is this force times the length of contraction. If we magnified a flea by a factor of 550, the cross section of its muscle would increase by 550^2 and the length of contraction would increase by 550. How high would this "superflea" be able to jump? (Don't forget that the mass of the "superflea" increases as well.)

So this is the set up I've come up with...

The initial gravity PE is 0 and the Initial and Final Kinetic energies are 0 as well... The final spring energy is 0 too so I'm left with

1/2kx^2 initial = mgy final y = .40 but I'm left with 3 other unknowns... If i knew them I could just multiply them all by 550 right?

HELP

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# Homework Help: Potential Energy (gravity & spring)

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