Current Events > Bet you can't solve this math problem!

(+) Yeah! (+)

Given a position, velocity, and acceleration use kelper's laws of orbit to plot the orbital ellipse of a low mass satellite

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69

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777

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Prove that a 2D space defined by the metric ds^2 = du^2 + u^2 dv^2 is either flat or not flat

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That's a second order differential equation and they're super hard to solve
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That fact that you said it was elliptical makes this kind of simple. You're basically asking us to find values of a & b subject to x^2/a^2+y^2/b^2=1 x(t)=x0 y(t)=y0 dx/dt=x1 dy/dt=y1. I'm not sure you even need to know the acceleration since you have 2 equations and two unknowns at this point.

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3.14

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FLOUR posted...

That fact that you said it was elliptical makes this kind of simple. You're basically asking us to find values of a & b subject to x^2/a^2+y^2/b^2=1 x(t)=x0 y(t)=y0 dx/dt=x1 dy/dt=y1. I'm not sure you even need to know the acceleration since you have 2 equations and two unknowns at this point.

An equation for an ellipse has 5 unknowns, also I don't know how you get the t into the x^2/a^2+y^2/b^2=1 equation.

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t is merely the independent variable since it sounds like a parametric equation. If I asked you to find the ellipse with center at the origin that contains the point (1,1) at time t with velocity -3 at that point, it shouldn't be hard to solve. The only question is if it's moving in a clockwise direction or not.

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Seriously though, I have the radius to the earth and initial velocity, also I have initial conditions in some x,y plane and yet I still can't figure out the equation of the location after time t, and i spent hours.

It's dumb I'm spinning my wheels on this so much because it should be easy.

The issue is that since I only have the radius of the earth I don't know where the center is or the other focal point.

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don't feel bad man I used to be pretty good with numbers I could multiply something like 973 x 468 in my head but I don't even know where to start with this lol. You're doing much better than I ever could.

I wonder if Mark Labbett could figure it out...?

@joe40001

There's a few forums you can find online that are something along the lines of "ask a physicist anything".

Those used to be my favorite reads on the internet.

fifteen

My roommates in undergrad were both aerospace engineering majors, and their description of their orbital mechanics classes made me glad that I will never have to go near the stuff.

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joe40001 posted...

An equation for an ellipse has 5 unknowns, also I don't know how you get the t into the x^2/a^2+y^2/b^2=1 equation.

Ha! You already gave us the answer! You suck, teach!
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Prove that this bullshit provided is a tensor

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