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The proposed Olympic sport seems like an elaborate reinvention of the standing long jump [1], just executed at an angle, and standing on a moving, unstable and

by avar 3y ago

The proposed Olympic sport seems like an elaborate reinvention of the standing long jump [1], just executed at an angle, and standing on a moving, unstable and elevated platform. Clearly the author expects (and the interesting mathematical problem is) that the athletes would restrict themselves to the swing itself to gain momentum. But nothing about the proposed rules prevents one from standing on the swing, and jumping forward at an angle on the backwards swing. 1. https://en.wikipedia.org/wiki/Standing_long_jump https://en.wikipedia.org/wiki/Standing_long_jump

deleted 3y ago
[deleted]
amluto 3y ago
> But nothing about the proposed rules prevents one from standing on the swing, and jumping forward at an angle on the backwards swing. That doesn’t sound like a very good strategy. The athlete is likely much heavier than the swing, and applying a backwards force to the swing will mostly just push the swing back. As mentioned elsewhere in the comments, one strategy is to jump off the swing at the farthest back point (so the jumping force is mostly balanced by the chain). Another is to jump up while the swing is moving forward. Some combination should work too.
- avar 3y ago
  If you think you can jump up, then you can also jump forward by jumping "up". it's just a matter of what angle the swing is at when you execute the jump. It's clearly trickier than a standing long jump, but mostly the same. One way to think about it is that it's similar to jumping from a stationary platform situated on the ground that's continually tilting between 45° backwards and forwards. The major difference is that even if the stationary platform is at 0° you can still get traction, but a swing will just be pushed back unless you're at the optimal angle, as you correctly point out. But if you time that jump exactly right the swing will behave like a rigid platform tilted 45° forward. At which point the proposed Olympic sport is just a standing long jump on a 45° elevated platform, with the added requirement of exquisite timing.
- Retric 3y ago
  An athlete’s maximum forward velocity is when the swing is closest to the ground. If you executed a standing jump at that moment your horizontal velocity remains the same and your vertical velocity comes from your jump height. I doubt this is better under most conditions, but it might win for some set of constraints.
- SamBam 3y ago
  > That doesn’t sound like a very good strategy. The athlete is likely much heavier than the swing, and applying a backwards force to the swing will mostly just push the swing back. I assume this is why GP specified "on the backwards swing." That is (as I understand it) when the swing is behind the crossbar, say at 45⁰ backwards. Then any pushing motion to propel the jumper forward would transfer through the chains to the bar, which is presumably stable. That said, I'm not sure if this is a good strategy, since you're starting further back. Yes, the world record for a standing jump is over 3 meters, but if you're starting 3 meters back it's not very good. (I'm assuming the measurement is from the crossbar, not from the origin of the jump, which would be very hard to measure.)
seventytwo 3y ago
Killjoy

by avar 3y ago

deleted 3y ago

[deleted]

amluto 3y ago

> But nothing about the proposed rules prevents one from standing on the swing, and jumping forward at an angle on the backwards swing. That doesn’t sound like a very good strategy. The athlete is likely much heavier than the swing, and applying a backwards force to the swing will mostly just push the swing back. As mentioned elsewhere in the comments, one strategy is to jump off the swing at the farthest back point (so the jumping force is mostly balanced by the chain). Another is to jump up while the swing is moving forward. Some combination should work too.

avar 3y ago
If you think you can jump up, then you can also jump forward by jumping "up". it's just a matter of what angle the swing is at when you execute the jump. It's clearly trickier than a standing long jump, but mostly the same. One way to think about it is that it's similar to jumping from a stationary platform situated on the ground that's continually tilting between 45° backwards and forwards. The major difference is that even if the stationary platform is at 0° you can still get traction, but a swing will just be pushed back unless you're at the optimal angle, as you correctly point out. But if you time that jump exactly right the swing will behave like a rigid platform tilted 45° forward. At which point the proposed Olympic sport is just a standing long jump on a 45° elevated platform, with the added requirement of exquisite timing.
Retric 3y ago
An athlete’s maximum forward velocity is when the swing is closest to the ground. If you executed a standing jump at that moment your horizontal velocity remains the same and your vertical velocity comes from your jump height. I doubt this is better under most conditions, but it might win for some set of constraints.
SamBam 3y ago
> That doesn’t sound like a very good strategy. The athlete is likely much heavier than the swing, and applying a backwards force to the swing will mostly just push the swing back. I assume this is why GP specified "on the backwards swing." That is (as I understand it) when the swing is behind the crossbar, say at 45⁰ backwards. Then any pushing motion to propel the jumper forward would transfer through the chains to the bar, which is presumably stable. That said, I'm not sure if this is a good strategy, since you're starting further back. Yes, the world record for a standing jump is over 3 meters, but if you're starting 3 meters back it's not very good. (I'm assuming the measurement is from the crossbar, not from the origin of the jump, which would be very hard to measure.)

seventytwo 3y ago

Killjoy