(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A planet of mass m orbiting the Sun(mass=[tex]m_s[/tex] along an elliptical orbit, with aphelion r1 and perihelion r2. Find the angular momentum of the planet relative to the centre of the Sun.

2. Relevant equations

Angular momentum, [tex]M=m(R\times v)=mvR sin\theta[/tex]

Distance from Sun to the planet, [tex]R=\frac{2{r_1}{r_2}}{(r_1+r_2)-(r_1-r_2)cos \theta}[/tex]

while [tex]\theta[/tex] is the angle of [tex]\overrightangle{R}[/tex] from the semi-major axis, which varies with time.

3. The attempt at a solution

Known that the angular momtentum is conserved along its motion, with v, R, and \theta varies with time but not sure that whether it is useful to derive the value of R, and I don't know how to relate this 3 variables together. Can anyone help me? Thank you very much!

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# Homework Help: Derive angular momentum of planet with elliptical orbit

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