1. The problem statement, all variables and given/known data 1 question: How much work must be done to launch a 100-kg object to a height of 2 x 10^3 kilometer above the Earth's surface? 2.A person with the mass of 10 kg jumps up and down on her mattress with a spring constant of 4.3 nK.m. She does this by applying a sinusoidal force at a frequency of 1 Hz. Assuming no dampening force exists, if her amplitude is 3 cm, what is the maximum force she places on the mattress? by the way, these are the only one I completely missed. He took off the maximum amount : ( And I still have no idea how to solve them. So I'm just wondering. 3. The attempt at a solution 1 question ( my attempt ) - okay, first I thought I would use the Vesc equation, but I simply got velocity out of it and I didn't know how to go from velocity to work. Then I had the idea, I would simply use the fact work is independent of the path and work = the change in potential energy so mgh = work thus, 100kg x 9.8m/s^2 x 2x10^6 mThus, I got 1.96 x 10^9 joules. Now, I knew this was too simply to be right, but I am still confused why this is the case. Why can't I use the fact work equals the change in potential energy in this case? 2 question: I used the equation A = (Fsmall o / m) /( w^2 - wsmall o ^2) and solved for w^2. then used the fact the max acceleration = Aw^2. Then to get the force. I simply used F=ma. and got 13N So, why is this wrong? I'm pretty sure, I converted to all the correct units. But, again, I thought this was too easy. Did I use an equation that wasn't applicable? Thanks in advance!