hi

how can i proof :

$\displaystyle

v=(mu/a)^{1/2} (1+e cosE/1-e cosE)^{1/2}

$

where $\displaystyle v =(v_{Ap}^2 + v_{peri}^2)^{1/2}$

if the planet orbit on ellipse ???

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- May 23rd 2006, 12:43 AM #1

- May 23rd 2006, 02:57 AM #2

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Originally Posted by**sweet**

we are guessing what you have been asked to prove, I assume it is:

$\displaystyle

v=(mu/a)^{1/2} \left(\frac{1+e\ \cos(E)}{1-e\ \cos(E)}\right)^{1/2}

$

but that leaves us guessing is $\displaystyle mu$ supposed to be $\displaystyle \mu$?

Is $\displaystyle e$ the eccentricity? $\displaystyle a$ the semi-major axis?

Also what is $\displaystyle E$?

We can guess but it is just making it more work for the helpers here.

RonL

- May 23rd 2006, 04:23 AM #3
ok

mu = $\displaystyle

\mu

$

e= the eccentricity

a= the semi-major axis

E=the eccentric anomaly

we want to proof

$\displaystyle

v=(\mu/a)^{1/2} \left(\frac{1+e\ \cos(E)}{1-e\ \cos(E)}\right)^{1/2}

$

if the planet orbit on ellipse ???

where

$\displaystyle

v =(v_{Ap}^2 + v_{peri}^2)^{1/2}

$

Thanks for helping me!

- May 23rd 2006, 06:21 AM #4

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Originally Posted by**sweet**

planet in its orbit and v as defined here is a constant, as are e mu and a

this cannot be true for almost all values of eccentricity.

Or have I misunderstood something?

RonL

- May 23rd 2006, 07:53 AM #5

- May 23rd 2006, 08:41 AM #6

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- May 23rd 2006, 09:08 AM #7

- May 23rd 2006, 09:11 AM #8

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- May 23rd 2006, 09:15 AM #9

- May 23rd 2006, 12:44 PM #10

- May 23rd 2006, 12:52 PM #11

- May 24th 2006, 12:45 PM #12Originally Posted by
**sweet**

-Dan

- May 24th 2006, 03:21 PM #13

- May 25th 2006, 03:37 AM #14

- May 25th 2006, 09:29 AM #15

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