1. The problem statement, all variables and given/known data A student jumping on a trampoline reaches a maximum height of h = 0.96 m. The student has a mass of m = 58 kg. What is the student's speed immediately before she reaches the trampoline after the jump in m/s? answer: 4.338 If, when she lands on the trampoline, she stretches the trampoline down d = 0.75 m, what is the spring constant k in N/m of the trampoline? h=0.96m m=58 kg d= 0.75 v=4.338 2. Relevant equations KE=(1/2)mv2 F=(1/2)kx SpringPE=(1/2)kx2 ΔPe=mgh W=fd cos(Θ) KE=-PE 3. The attempt at a solution I have had a gruesome time trying to understand spring related questions. First I took F=-kx and solved for k, leading to -k=F/x leading to k=mg/x. This is wrong however, because the force of the trampoline is greater than the force exerted by gravity on the person. so in the equation we have 2 unknowns, k and f. So I took formula KE=-PE KE=(1/2)mv2 SpringPE=(1/2)kx2 leading to (1/2)mv2=-(1/2)kx2 thus -mv2/x2=k This didn't give the correct answer and I'm not sure why. Is KE also supposed to inclued the KE of the falling person?