Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Orbital Kinetic Energy



E = v^2/2 - mu/r = h^2/(2rp) - mu/rp

rp = radius at periapsis
mu = GmM

rp=a(1-e) and h=sqrt(mu p) = sqrt(mu a(1-e^2))

By substitution, E = -mu/(2a)

I hope that helps,
Peter Schoch

Brian Blais wrote:

Hello,

I was wondering if anyone knew of a calculation showing that the kinetic
energy of an object in a circular orbit is equal to half of the potential
energy, where the calculation does *not* use acceleration or force at all. Is
there an argument for this based purely on energy concepts? It occurred to me
that there should be, but I can't think of it.

thanks,

Brian Blais

-----------------

bblais@bryant.edu
web.bryant.edu/~bblais