Best Answer Grimbal, 30 November 2013 - 03:02 AM

Welcome to BrainDen.com - Brain Teasers Forum. Like most online communities you must register to post in our community, but don't worry this is a simple free process. To be a part of BrainDen Forums you may create a new account or sign in if you already have an account. As a member you could start new topics, reply to others, subscribe to topics/forums to get automatic updates, get your own profile and make new friends. Of course, you can also enjoy our collection of amazing optical illusions and cool math games. If you like our site, you may support us by simply clicking Google "+1" or Facebook "Like" buttons at the top. If you have a website, we would appreciate a little link to BrainDen. Thanks and enjoy the Den :-) |

Guest Message by DevFuse

Started by bonanova, Nov 24 2013 08:37 AM

Best Answer Grimbal, 30 November 2013 - 03:02 AM

Spoiler for If the tamer runs on the perimeter

Spoiler for If the tamer is not on the perimeter

18 replies to this topic

Posted 30 November 2013 - 06:46 AM

The good news is that using equations for a more efficient approach strategy by the lion as the trainer runs around the perimeter doesn't require trig functions. The bad news is that I nonetheless end up with a differential equation that I can't see how to solve.

But I can show that the lion is able to catch the tamer, albeit with a much less optimal approach.

Spoiler for redo of the lion's approach path

But I can show that the lion is able to catch the tamer, albeit with a much less optimal approach.

Spoiler for

Posted 02 December 2013 - 03:06 PM

Spoiler for If the tamer is not on the perimeter

Hi Grimbal. Care to share the tamer's escape path that precludes being caught in finite time?

- Bertrand Russell

Posted 02 December 2013 - 03:10 PM

Spoiler for my take

- Bertrand Russell

Posted 02 December 2013 - 11:30 PM

I thought lions could pounce. But even if that is not allowed, the lion still must eat.

Spoiler for Change of plan for the hungry lion

**Edited by Prime, 02 December 2013 - 11:32 PM.**

Past prime, actually.

Posted 03 December 2013 - 12:06 AM

I thought lions could pounce. But even if that is not allowed, the lion still must eat.[/size]

Spoiler for Change of plan for the hungry lion[/size]

Yes the lion can pounce, I.e. Feet can leave the ground. His top speed is still 1 radius/second.

If the tamer's minutes, or seconds, are measured, how long does he have, with starting locations at center (lion) and perimeter (tamer)?

- Bertrand Russell

Posted 03 December 2013 - 07:27 AM

If I understand correctly, the Zeno argument says that (going in the reverse direction) when you are at the perimeter the change in the lion's distance from the center over time equals zero so there is no way to get out from the perimeter.

Would this be the same as considering the function y = x^{2} and saying that dy/dx at x=y=0 is zero, so there is no way for the y value to increase and ever leave the x-axis? Since y is not changing and x is the square root of y, would that also imply that x cannot change and so the function can never even leave the origin at all?

Would this be the same as considering the function y = x

Posted 03 December 2013 - 10:55 AM

If I understand correctly, the Zeno argument says that (going in the reverse direction) when you are at the perimeter the change in the lion's distance from the center over time equals zero so there is no way to get out from the perimeter.

Would this be the same as considering the function y = x^{2}and saying that dy/dx at x=y=0 is zero, so there is no way for the y value to increase and ever leave the x-axis? Since y is not changing and x is the square root of y, would that also imply that x cannot change and so the function can never even leave the origin at all?

Yes, sort of.

I don't have the equations and I expected the lion would approach the edge of the cage asymptotically, never actually reaching it. But now I think that's wrong. It is more like a parabola, and the lion's path is simply tangent to the circular edge, touching it at a single, well-defined point. The path has finite length and is retraceable.

- Bertrand Russell

Posted 03 December 2013 - 01:31 PM

Spoiler for If the tamer runs on the perimeter

Spoiler for If the tamer is not on the perimeter

Spoiler for Grimbal has the path shape

I'm marking the puzzle solved but invite Grimbal to describe an off-perimeter escape strategy for the tamer.

**Edited by bonanova, 30 January 2014 - 02:01 PM.**

Describe another capture path and pose a new calculation

- Bertrand Russell

Posted 03 December 2013 - 05:37 PM

I like happy endings. And that uncomplicated trajectory is nice too.

Past prime, actually.

0 members, 0 guests, 0 anonymous users