# Gravitation between the Moon and the Earth: physics project

Omg i think its finally working i am so dumb i was changing the acceleration value now i am keeping "a" constant and only changing the ax and ay based on position currently dragging down 1 cell at a time since they all depend on each other

ok think i got it
now i have no idea how to graph this data, that's the next challenge

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moon has escaped orbit

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this is looking good to me, bvu thank you for all the help! i finally got it somewhat working
(the name "position y" is misleading) this is the x and y coordinates plotted

beautiful :')

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BvU
BvU
Homework Helper
In fact it shouldn't come out as a circle with the set of equations and initials we had. Has to do with reduced mass.

A physics complication. There's also a math complication: an issue with simple forward Euler for this kind of problem. But you learned a great deal which is far more important than getting the 'right' result.

Good luck with the test. I hope you did get some kip

isukatphysics69
In fact it shouldn't come out as a circle with the set of equations and initials we had. Has to do with reduced mass.

A physics complication. There's also a math complication: an issue with simple forward Euler for this kind of problem. But you learned a great deal which is far more important than getting the 'right' result.

Good luck with the test. I hope you did get some kip
Thank you, i will sleep after this report and study tommorow before the test, already went over the whole practice exam once

BvU
Homework Helper
now i am keeping "a" constant and only changing the ax and ay based on position
Sorry for the bummer, but that isn't the idea of the exercise.
currently dragging down 1 cell at a time since they all depend on each other
in principle row n only depends on row n-1. That's forward Euler for you, the often self-quoted recipe$$x_n = x_{n-1} + v_{x, n-1} * dt \\y_n = y_{n-1} + v_{y, n-1} * dt \\v_{x, n} = v_{x, n} + a_{x, n-1} * dt \\v_{y, n} = v_{y, n-1} + a_{y, n-1} * dt$$

gotta face the drill now

Sorry for the bummer, but that isn't the idea of the exercise.
in principle row n only depends on row n-1. That's forward Euler for you, the often self-quoted recipe$$x_n = x_{n-1} + v_{x, n-1} * dt \\y_n = y_{n-1} + v_{y, n-1} * dt \\v_{x, n} = v_{x, n} + a_{x, n-1} * dt \\v_{y, n} = v_{y, n-1} + a_{y, n-1} * dt$$

gotta face the drill now
aw crap what
its not possible at this point, its 4 am and due tommorow

aw crap what
its not possible at this point, its 4 am and due tommorow

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i am attempting to fix it

i think i just fixed it, if you come back plz let me know
oh my lord i think i may have just fixed it

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Graphs are updated and still looking good, not much of a change in the graphs as i go lower the acceleration is decreasing

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I think this is what i have to go with regardless. i gave it my best shot now have to move on and will read feedback if given from prof

this is screwed

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BvU
Homework Helper
Kudos for your tenacity ! Hope the test went well...

I mentioned you in a related thread . A lot of good reading in the pdf link in post #5.

There also is a recent earth-moon thread here:
So I was messing with VPython, trying to create an Earth-Moon System. I got the actual gravity to work, and can create some nice ellipical orbits. However I run into trouble trying to make the actual (almost) circular orbit of the moon.
...

Definitely failed that final exam but my test average this semester was 84 over 6 test so I think I will pass the course. Very disappointed in self but how on Earth ani supposed to pass a final that has 2/6 questions that we covered last week. So I answers 3/ 6 questions and we were supposed to answer 4/6 to have a chance at full credit plus this project lack of sleep and food was a recipe for disaster plus I'm just a complete moron but whatever I failed sometimes you fail

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BvU
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Definitely failed that final exam but my test average this semester was 84 over 6 test so I think I will pass the course. Very disappointed in self but how on Earth ani supposed to pass a final that has 2/6 questions that we covered last week. So I answers 3/ 6 questions and we were supposed to answer 4/6 to have a chance at full credit plus this project lack of sleep and food was a recipe for disaster plus I'm just a complete moron but whatever I failed sometimes you fail
Sure, and the world is a bad place etcetera
You're entitled to a bit of disappointment, not to a lamentation like this and self depreciation. Consider it a learning experience: planning, sleep, food, whatever is imoporant too and can only be ignored at a price. You come out of this better than you were. Cheer up.
Find a real shoulder if necessary. PF doesn't provide effectively in such matters

isukatphysics69
Sure, and the world is a bad place etcetera
You're entitled to a bit of disappointment, not to a lamentation like this and self depreciation. Consider it a learning experience: planning, sleep, food, whatever is imoporant too and can only be ignored at a price. You come out of this better than you were. Cheer up.
Find a real shoulder if necessary. PF doesn't provide effectively in such matters
Alright man thank you, I'm sure i will be back posting 10 threads per week again in the fall for physics 2. Have a good summer
Sure, and the world is a bad place etcetera
You're entitled to a bit of disappointment, not to a lamentation like this and self depreciation. Consider it a learning experience: planning, sleep, food, whatever is imoporant too and can only be ignored at a price. You come out of this better than you were. Cheer up.
Find a real shoulder if necessary. PF doesn't provide effectively in such matters
thank you for all the help, I'm sure I will be back for calculus 3 in a few weeks. Take care :)

BvU