Question

Your friend provides a solution to the following problem. Evaluate her solution. The problem: Jim (mass 50 kg) steps off a ledge that is 2.0 m above a platform that sits on top of a relaxed spring of force constant 8000 N/m. How far will the spring compress while stopping Jim? Your friend's solution: (50kg)(9.8m/s2)(2.0m)=(1/2)(8000N/m)x x=0.25m4.

Answer 1

Answer:

No its wrong

Correct compression is 0.41

Explanation:

After jumping from 2m height on spring attached platform platform is compressed a distance x(let).

So work done by gravity on Jim is converted into spring potential energy.

k=8000 N/m

mass of Jim =50 kg

$\frac{1}{2}k(x)^{2} =m*g(2+x)$

$\frac{1}{2}8000(x)^{2} =50*9.8(2+x)$

$8.16x^{2} =2 +x$

Solve this quadratic one solution is positive and other is negative.

positive one is our answer = 0.41 m