- #1

bfusco

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## Homework Statement

A 55 bungee jumper leaps from a bridge. She is tied to a bungee cord that is 11 long when unstretched, and falls a total of 31 .

a)Calculate the spring constant of the bungee cord assuming Hooke's law applies.

b)Calculate the maximum acceleration she experiences.

## The Attempt at a Solution

first i drew out the problem in 3 sections. the first (A) the jumper on a cliff 31 m above h=0, then i drew (B) the jumper 11 m below the cliff because that is the length of the rope, and the third (C) the jumper at h=0, all the way at the bottom.

a)= 84 N/m

-to get this i solved for velocity at B by setting the energy at A = energy at B. mgh(at A)=1/2mv^2+mgh(at B) and got v=14.7 m/s. then i used Energy at B=Energy at C, mgh(at B)+1/2mv^2=1/2kx^2 and got k=83.5 N/m.

b)i know the point of greatest acceleration can't be at A, at B its simply acceleration due to gravity, and at C the jumper is at h=0 and has a moment of no movement, so no acceleration. however the answer isn't 9.8.