Alright, fellows. I'm in a deep one...

Alright, fellows. I'm in a deep one. I need to find the turning points (points where [math] \dot{r} = 0 [/math] ) of pic related.

The result should be given by the equation in pic, but the one I'm getting has minus at the second term in the second parenthesis.

Can anybody tell me where am I wrong?

Also, to use the initial conditions (r0, v0) to express the constants arising from the integrals of motion.

Appreciate your help

>has minus
I meant to say that it has plus in the second term of the second parenthesis.

bampo

>Doesn't post the complete problem.
>Doesn't post the whole solution attempt.
>Can anybody tell me where am I wrong?

Do you think people on Veeky Forums are clairvoyant?

>tfw this problem was in my classical mechanics test

Show us your work OP, I don't feel like doing everything from the start

Well, just speaking for myself, I don't know what r is or what is happening in the picture.

If you can't figure out what's going on just from the pic then I don't need your help.

I don't feel like TeXing all that shit. Basically, I've got the correct Lagrangian in polar coordinates, I'll use the initial conditions to find express the integrals of motion.

Energy of the system came out as

[math] E = \frac{1}{2}mv_{0}^{2}r_{0}\dot{\varphi} [/math]

When used, this energy gives the correct result for the equation of the turning points, but I'm getting the plus sign in the second term.

Whic

Slash that quadratic initial speed. Should be just [math] v_{0} [/math]

Lol
> if you don't remember what every first year physics problem is about from picture alone you can't possibly help
Hope you find someone who meets your standards.

>first year problem
Get lost

PS. Pretty sure the only ones to meet those standards by the way are probably people who are also currently doing the problem, or maybe did it last assignment.

I said get lost, brainlet

v_0 is an initial condition, not a variable.

[math]l = m/2(r'^2) + M/2(r'^2) + Mg(r_0 - r)[/math]

I figured you'd be happy for some bumps so you could find your unicorn.

Don't need one. Alredy finished it. It's pretty pathetic that most of Veeky Forums is incapable of even discussing the problem.

That's because you basically said, I have this letter "a" and it's supposed to be part of a word, anyone know which one?

You're a brainlet and you don't know shit about classical mechanics if I even have to tell you what those letters in the picture mean.

FUCKING LOL. I can't believe you are this stupid and are calling other people brainlets. It was an analogy, I wasn't saying that you didn't say what the letters meant, I was saying that you didn't give any of the information to solve the problem. Holy fuck, I can't believe you just said that.

triggered as fuck lol

get back to klass, kiddo

No, it was hilarious, it was a revelation to how stupid you actually were. I guess the brainlet thing is just a defense mechanism. It also explains why you would post a problem with barely any information.

Both of u are brainlets, I'm the real Veeky Forumsentist here. Ask me anything.

I'm missing something here. What is the difference between r and r0? r0 is the origin of r as in (r=0m)?

Also, are you sure Mgr^2 isn't Mgr^1?

Yes, it looks like you distributed the r-r0 factor but then kept it as a separate factor as well.