1. The problem statement, all variables and given/known data This is the second part of a two part question. The first part asked for the maximum force that can be applied to a bone with minimum cross-sectional area is 3.0cm2, Young's modulus 1.4 × 1010 N/m2, and can withstand a 1.0% change in length before fracturing. I calculated it to be 4.2x108 N. This is the part I'm struggling with: (b) Estimate the maximum height from which a 50 kg student could jump and not fracture her tibia. Take the time between when she first touches the floor and when she has stopped to be 0.03 seconds. 2. Relevant equations change in momentum = net force * change in time p = mv v = at (or possibly a different kinematics equation?) 3. The attempt at a solution Just after the student hits the ground, the ground exerts and equal and opposite force of -mg = 490N on the student: p = 490 * .03 = 14.7 I am confused about how to relate the maximum force I calculated earlier to the force of the ground on the student when she lands. The force on the student seems like it should be 490 just after she impacts no matter how far she fell, but that obviously isn't the case. I asked my professor for help and he said that it's the small time interval that results in the force getting so large, which I sort of understand, so I tried this (with the ultimate goal of getting the total time it took the student to reach the ground so I could solve for the height of the drop): 14.7 = 4.2 x 108 * t But that comes out even smaller than the impact t. So just in case I had done things backwards, I tried: 50 * v = 4.2 x 108 * .03 But that resulted in a time interval that was several hours long, which is also unreasonable. I am generally very confused about momentum and the force can change on impact. I understand that exerting the force over a longer time interval will make the force at a given time smaller and vice versa but I still can't figure out how to solve this problem. Thank you.