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Physics/Calculating orbit eccentricity

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Question
This is the formula to calculate orbit eccentricity
e = SQRT[1+2E(h^2)/M^2]
where
E(total energy) = v^2/2 - M/r
h = r*v(t)is angular momentum
v(t)= tangential component of the velocity
v = velocity vector
r = radial distance from center of mass
If i want calculate the eccentricity of Earth in its rotation around the Sun i have to use this formula.
I already know this value e = 0.017
whereby
e = SQRT[1+2E(h^2)/M^2] = 0.017
My problem is that i'm not able to do these calculations...
May be you can help me showing for extended calculations.
Marianna

Answer
I don't answer homework questions, but here you don't even have the right equations.  Your units in your formula for total energy don't make any sense at all and aren't even compatible. Your angular momentum formula doesn't have a mass in it.  There's a wikipedia article that can lead you to correct equations for orbital eccentricity, I suggest you start there: https://en.wikipedia.org/wiki/Orbital_eccentricity

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Dr. Stephen O. Nelson

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I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

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I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

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Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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