Physics, Astronomy & Cosmology / Re: If you throw a mouse or elephant at someone in space, which will move them more?« on: 07/01/2020 21:59:58 »
It's actually just complicated algebra, but I did my reply-12 thing by guessing, and hit it in my 2nd guess, the first guess being 50kg. I had a hunch and it turned out to be correct. This is the case of the 2nd guy returning the projectile with the same energy as the first throw, not at the energy of the incoming projectile.Quote from: HalcWhat is the cutoff mass for [projectile returning to first person]? This is not the same mass as the answer to my post 12 question.I don't know how to calculate that without using trial and error. You likely use calculus
One more thing on a different but related issue. If I wanted to write a snooker simulation but with variable-mass balls and with the angles of impacts leading to the balls going off at different angles, can the same maths as above still be used just by breaking things down into vectors?Snooker is complicated. It isn't frictionless balls in a vacuum, which is actually pretty easy arithmetic. Snooker has to deal with table friction, especially immediately after the impacts where the balls are moving at a different rate than their spin. That spin deflects both balls from their initial trajectories, and I'm not up to the challenge of computing the angular inertias and funny spins with non-horizontal axes.
Yes, it's quite easy to do with frictionless balls in space. Target ball moves directly away from its impact point and incoming ball is deflected in a way that preserves momentum and energy.
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