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madking153
Dec11-05, 03:08 PM
hi,

if i have mass possess potential U(x)=-Gm1m2/(x^2+y^2+(kz)^2 )^1/2 , i said angular momentum of z is conserved but not angular momentum of x , y .. is it correct ?

what else is conserved ? energy ?

Physics Monkey
Dec11-05, 03:18 PM
Yes, the z component of angular momentum is conserved, but the other two are not unless k = 1. As for other conserved quantities, what do you think? You have a potential ...

dicerandom
Dec11-05, 03:22 PM
Are you familliar with Lagrangian mechanics? If so you can use Noether's Theorem to calculate conserved quantities:

http://www.mathpages.com/home/kmath564/kmath564.htm

It may very well be quicker to just use your physical intuition though.

madking153
Dec11-05, 06:03 PM
My thought : angular momentum of z component and the energy of the system is conserved ... Pls tell me if there are more quantities are conserved
thanks

madking153
Dec11-05, 06:05 PM
no i am not familiar to Langrage mechanics - will learn next 2 months

madking153
Dec12-05, 05:31 PM
So i am correct ?? angular momentum of z and energy are conserved ?