Planet Velocity at Aphelion: Find the Answer

Thread starter Ready2GoXtr
Start date Jul 15, 2008
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Planet Velocity

AI Thread Summary

To find the velocity of a planet at aphelion, conservation of angular momentum is applied, where the initial angular momentum (IiWi) equals the final angular momentum (IfWf). The variables involved include mass (m), velocity (v), and radius (r) of the planet. The planet's distance from the Sun at perihelion is 175 million km with a velocity of 40 km/s, while at aphelion, it is 250 million km. The discussion emphasizes the need to define angular momentum in terms of these variables to solve for the unknown velocity at aphelion. Understanding these principles is crucial for accurately determining the planet's speed at its farthest point from the Sun.

Jul 15, 2008

Ready2GoXtr

Homework Statement

At perihelion a planet in another solary system is 175 x 10 ^ 6km from its Sun and is traveling at 40km/s. At aphelion it 250 x 10 ^ 6 km distant and is traveling at?

Homework Equations

IiWi = IfWf

The Attempt at a Solution

What do i do?

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Jul 15, 2008

Dick

Science Advisor

Homework Helper

Use conservation of angular momentum as you are trying to do. What are I and W in terms of mass m, velocity v and radius r of the planet?

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