Recent content by amondellio

@BiGyElLoWhAt I was hoping you might take a look at this problem and see if it looks right. According to the answer key my professor sent out today, the velocity is correct but the acceleration is not. My professor has a=80.04m/s^2

thanks for the help @BiGyElLoWhAt. I don't know why I was having such a difficult time with this problem.

I just don't get what to do without time or the final x position

I don't know what you mean

does this look right?

I think I've solved it with the kinematics equations, but the problem is part of a practice test and my professor wants me to show my work using calculus for all problems. I'm so confused.

I haven't taken calculus in 5 years, so I don't really think I would say I know calculus haha how would I derive the vector position function you're talking about?

Here's a better picture of the problem, sorry

Homework Statement I've attached a picture of the problem Homework Equations I'm assuming I need to use ads=vdv The Attempt at a Solution I've attached a picture of my attempt at solving the problem, but I really have no idea what I'm doing. I'm really having a hard time in this...

I figured out the solution yesterday, thanks for the help. I've posted a picture in case anybody is interested.

So (.05*9.81*-2) - (.02*9.81*2) = -.5886 But you said: Your -0.5886 number has the right magnitude for the net change in PE. Note that the change in KE must have the opposite sign, since what's lost in PE results in a gain in KE. So that sounds like it shouldn't be -.5886, but instead .5886?

Uim1 = .05*9.81*2 = .981 Uim2 = .02*9.81*2 = .3924 Ufm1 = .02*9.81*0 = 0 Ufm2 = .02*9.81*4 = .7848 ΔU = Uf-Ui = ? For the final PE calculations should I be using Δh (m1= -2/m2= +2) instead of h (m1= 0/m2= 4)?

I understand that the blocks are moving different directions but mgh are each positive for both blocks so I don't understand what causes the negative.

That just made me even more unsure of what I'm doing. I appreciate your help so much, is there anyway to "dumb it down" further? I have been working on this problem for hours I'm getting so frustrated.

ΔU=-0.7848-1.3734=-2.1582 and looking at that it seems like that's way too big of a difference. Should I switch the positive direction of motion? So that I have ΔU=0.7848-1.3734=-0.5886 that seems much more likely to me? Oh man I'm so confused by this