Recent content by cycam

...bump!

Homework Statement Prove the following useful fact: the least-squares fit for a line through any set of points (x_1,y_1) ...,(x_N, y_N) always passes through the "center of gravity" (x-bar, y-bar) of the points, where the bar denotes the average of the N values concerned. [Hint: you know...

Oh man! I know, I've been stuck on this problem for hours! I think it is lame. I'll give you a heads up if I get anything.

OH sorry! Thanks for the info; I solved part A already.

Okay, that is what I was stuck on; L. I know L is measured on the surface of the planet, like arclength, and s = rtheta. But I don't know if I can get the r from that since we don't have theta? for the apparent weight, do we use w=Gm_Em/r^2 ?

I am having trouble with the first portion of the problem too. Do you think you could lead me in the right direction, Peach? Are you supposed to change L into some form of r, or is L = r? I'm not quite sure what to do. Any help would be great. Thanks in advance.

ok, i got it. thank you =)

so is it MR=v_delta/v_exln?

Let me do the math really quickly and i'll show you what I got.

updated the original question.

Yes, it appears that it is starting from rest. How would I go about finding the mass ratio? Also, the log equation? How do I go about finding the mass of the rocket? (is that even the right question to ask)

It doesn't say that it has to be which i would assume it shouldn't be. All I know about the question is what you see. So to answer your question, i don't know. I was hoping someone would be able to answer that lol.

Homework Statement A single-stage rocket is fired from rest from a deep-space platform, where gravity is negligible. If the rocket burns its fuel in a time of 50.0 s and the relative speed of the exhaust gas is v_ex=2100 m/s, what must the mass ratio m_{0}/m be for a final speed v of 8.00 km/s...

is there possibly a different way to write the solution? I've thought about this problem a lot and although the answer is right, i know I'm missing something stupid.

No need to feel dumb, it took me HELLA long to figure that out lol. It wasn't until my boyfriend pointed that out that I realized what it was ha ha. I always forget not to overlook the obvious things in focus on the complexity