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BIO Compressing the Ground A running track at Harvard University uses a surface with a force constant of 2.5 × 105N/m. This surface is compressed slightly every time a runner’s foot lands on it. The force exerted by the foot, according to the Saucony shoe company, has a magnitude of 2700 N for a typical runner. Treating the tracks surface as an ideal spring, find (a) the amount of compression caused by a foot hitting the track and (b) the energy stored briefly in the track every time a foot lands.
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