Dumping a huge bag of plastic balls onto an escalator

boing
41

Every once in a while a random higher-energy ball reaches escape velocity and rolls away from the bottom. If the balls were bouncier I think this decay would occur faster. Does the bounciness correlate to the half-life of the system? And what’s the SI unit for bounciness anyway?

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42

Presumably the bounciness is related to the amount of kinetic energy that the ball has on leaving the surface. Any added energy is just the GPE from the elevator, while escape velocity would have to work against the elevator moving in the opposite direction and the dissipated energy from hitting the elevator and other balls.A bouncier ball would retain more energy to convert back into kinetic energy and would hit the elevator and other balls fewer times on the way down (and out). A beanbag would never make it.

43

That guy’s got a lot of cojones.

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44

What darkhelmet169 said…

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But of course!
On the serious side – I am more than happy to interpret this as the kinetic art version of what in musical composition is known as a Perpetuum Mobile.

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I was going to make a comment about Brownian Motion, but then noticed none of the balls were brown.

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47

Or named Ian.

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48

There’s some huge scary escalators to and from the parking garages at Disneyland as well.

I have a small phobia of escalators and I am pretty unhappy when we get parked on the 6th floor.

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That’s fair; I have a phobia of Disneyland, so we’re even.

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The Tigger (Tg)

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51

I think you’re thinking about this too hard. :smile:

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The longest escalators in the Western Hemisphere are used in the Washington DC Metro System, though, frankly, I’m not sure why you might have occasion to visit Wheaton (230 ft) However, you might visit the National Zoo. The closest Metro Station–Woodley Park-- has a 205 foot long escalator.

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Much more precise than the old-fashioned “Baby Boy” scale.

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55

Um… you are aware that resistance is futile?

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Popcorn

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57

Pro tip - don’t slide down the handrail unless you are wearing fireproof black pants…

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58

Is this from experience?

I know that the handrails are absolutely filthy-- enough that one might want to wear gloves.

59

Thanks. I finally get it. What Cory’s saying is that it’s like a perpetual motion machine because you perpetually keep putting energy in yet get no result. Like, you could burn coal and oil forever to run the escalator and the balls won’t go anywhere, so it’s perpetual motion.

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I remember there being really long/high (3-4 stories) intimidating escalator in the National Bowling Stadium in Reno, NV (yeah, I know, step-dad is really into bowling).

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I will not visit any of those, thanks. But you have given me some places to avoid.