Can you find two different constants by Noether's theorem

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qinglong.1397
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Homework Statement



Consider a 3-dimensional one-particle system whose potential energy in cylindrical polar coordinates [tex]\rho[/tex], [tex]\theta[/tex], z is of the form V([tex]\rho[/tex], k[tex]\theta[/tex]+z), where k is a constant.

Homework Equations


The Attempt at a Solution



I already find a symmetric transformation:
[tex]\rho '[/tex]=[tex]\rho[/tex], [tex]\theta '[/tex]=[tex]\theta[/tex]+[tex]\theta_0[/tex], z'=z-k[tex]\theta_0[/tex].

Can you help me find at least another one? Thank you!
 
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No body can do it?
 
Hurkyl said:
And what have you done on the problem? It is strictly against policy to just hand out answers -- it's cheating and does little to help the student learn.

I found one solution, as mentioned in the first post. I just do not know how to find the other one. I need your help. Just hint. Thanks!
 
This is a problem from Classical Dynamics: A contemproray approach by Jose. I think it is not very possible that it is wrong.
 
Ah yes... problem 3.11 by any chance? Now that you mention it, I remember doing that one for a homework assignment once upon a time :wink: and I seem to remember having the same difficulty with it.

Try thinking about symmetries in time, since you've already considered the three spatial coordinates.
 
diazona said:
Ah yes... problem 3.11 by any chance? Now that you mention it, I remember doing that one for a homework assignment once upon a time :wink: and I seem to remember having the same difficulty with it.

Try thinking about symmetries in time, since you've already considered the three spatial coordinates.

Oh, yeah. I never thought about that. Thank you very much!