Recent content by skatj

Mass is of the entire system, which is 7kg, not 3kg.

I don't think gravity does any work on M1, (mgh)final = (mgh)initial. No change in potential energy, no work done.

I only skimmed the problem, but isn't initial v given?

I think it means that if F is held constant over a period t, then so would acceleration. Knowing that, you can find final V using simple kinematics, given a and t.

So that's the equation for terminal velocity, and if the terminal velocity will always be the impact speed, then I need to find out how to make terminal velocity low enough so the force is under the maximum survivable force taken by a human body right? In that equation, m = mass, g =...

I'm not familiar with that equation, sorry :( I couldn't find it on google either

Yea that makes a lot of sense! Thanks. How would I know the impact time though? Would I just generalize it to something very small? (Btw, since a skydiver will reach terminal velocity, then doesn't that mean after a certain altitude the force won't increase because he's already hit a max speed?)...

Exactly, which is why I'm saying I don't understand how the force of impact is calculated with F = MA if the A = 9.81 in freefall, because if A always equaled 9.81, then how does the altitude get factored in? I'm missing something here!

Homework Statement My physics teacher has given me a project to design some kind of device to allow landing from 5,000 feet without a parachute. So far we have been taught nothing but forces, velocity, acceleration, displacement, and vectors so I'm kind of at a loss. First step of the project...