A comet moves in an elliptical orbit around the sun. It's closest approach to the sun is 0.59 AU and its greatest distance form the sun is 35AU. If the comet's speed at its closest approach is 54 km/s what is the speed when it is farthest away? Angular momentum is conserved and the gravitational forec eserted by the Sun has a moment arm of zero.(adsbygoogle = window.adsbygoogle || []).push({});

Here's what I did...

[tex]I_{initial} \omega_{initial}=I_{final} \omega_{final}[/tex]

moment of inertia is always the same...

[tex]\frac{v_i}{r_i}=\frac{v_f}{r_f}[/tex]

[tex]\frac{54000m/s}{88262020000m}=\frac{v_f}{5.23593E12m}[/tex]

[tex]v_f=3203419m/s[/tex]

did I do this correctly?

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# Homework Help: Comet's speed

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