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thx for ur time

- Thread starter matrix_204
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thx for ur time

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enigma

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The generalized form is called the Vis-Viva equation:

[tex]V=\sqrt{\mu*(\frac{2}{r}-\frac{1}{a})}[/tex]

Where [itex]\mu[/itex] is G*M or 398600.4 km^3/sec^2 for Earth,

r is the distance from the center of the Earth and

a is the semimajor axis of the ellipse.

You'll see that for a circular orbit, a = r for all points on the "ellipse" and you get the expected [tex]\sqrt{\frac{\mu}{r}}[/tex]. You can also get the escape velocity by plugging in infinity for a.

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1. Conservation of Angular Momentum

2. Conservation of Energy at any moment

Writing the above equations as function of r,v

and calulate r or v whatever required

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enigma

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Do you understand it? The way you worded that, it sounds like you didn't.Originally posted by matrix_204

even though in high school we haven't learned that formula yet,

It really isn't any more difficult than sqrt(mu/r). a is half the distance of the longest line in the ellipse, r is the current position. Plug and chug.

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Yes those two equations are basic foundation for deriving formula

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Each planet moves around the sun in an elliptical orbit. the orbital period, T,of a planet is the timeit takes the planet to go once around the sun. the orbital period of a planet is proportional to the 3/2 power of the length of its semi-major axis. what is the orbial period (in days) of Mercury whose semi-major axis is 58 million km? what is the period (in years) of Pluto whose semi-major axis is 6,000 million km? the semi-major axis of the Eart is 150 million km.

how do you solve this

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