Gravity

[STxAxTIC]

Hello all,

As sort-of a Part 2 to follow the discussion of conic sections here, https://www.qb64.org/forum/index.php?topic=2621.msg118444, I bring you my latest summary of classical gravity. This is a horribly dense read, I figure the audience for this can be counted on one hand. Nonetheless, for anyone doing gravity simulations, trajectories, celestial motions, and so on - you can fact check against this.

Oh, and there are a few problems at the end  - incidentally we solved the last problem here over a year ago: https://www.qb64.org/forum/index.php?topic=1061.msg102487

Now you can do that problem with no computer at all. See below.

[Qwerkey]

Wow!  Another tour de force!

the audience for this can be counted on one hand.

That'll be Ashish and...  Maybe not: that'll be Ashish!

At least you didn't do it in 3D, with nablas and dels all over the place.

[STxAxTIC]

Qwerkey it is in 3d, read carefully!

Actually we're both right - one of the first things I do in here is prove that all central force motion is planar, which actually does make it an effective 2D problem. And honestly this isn't super hard, the hardest math going in is just derivatives and integrals, so maybe... Idk... calculus 2 reading level required?

[Qwerkey]

Qwerkey it is in 3d, read carefully!

Actually we're both right - one of the first things I do in here is prove that all central force motion is planar, which actually does make it an effective 2D problem.

Oh yes, I understood that, of course.