Have you seen these guys?

 

These guys are quite good. I'd seen the "Thunderstruck" one before, not the second though.

 

These guys are quite good. I'd seen the "Thunderstruck" one before, not the second though.

They have quite a few, all rock/metal stuff with cellos.

 

Then there's the bag pipes. Each one of the pipers here have many videos.

 

 

OK, we're doing music things. I bet the code for this took a while to write.

 

Last one:

 

Here's one @MaxHeadRoom might like:

 

New rotary engine design being tested for applications.

 

A bit long of a video but it's pretty cool. Especially to music lovers.

I'd like to see Pete Townshend use that guitar in a concert... and then try to smash it in the end...

 

Last one:

Shades of Floppotron, which was made many years ago. Floppotron artists has many songs out there...

 

 

 

 

Does a falling slinky defy gravity?

 

 

Does a falling slinky defy gravity?

I'm sure it does not, but it definitely shows a behavior you wouldn't predict beforehand. Cool.

 

it definitely shows a behavior you wouldn't predict beforehand.

You're right. I wouldn't have predicted that. That's why I thought it was pretty cool to watch. But if you stop and think about it - it makes perfect sense. Not in what the guy was saying about "signals" but from a balance of force point of view. The slinky is wanting to retract itself. Letting go of the top means it will fall faster than 1G. In order for the bottom to remain stationary while the top collapsed would predict there's a 2G acceleration counteracting against the center of gravity resulting in the CG falling at 1G. Meaning the bottom is retracting upwards in respect to the CG. But given that the bottom is acting in opposite concert to the CG, it should appear to hang motionless in space.

New theory on the theory of everything - - - Spring Theory.

 

I can remember doing that with a slinky as a kid. I just thought it looked cool. I didn't know enough then to ponder whether or not it "defies gravity" but now that I do, I do.

I think it "defies gravity" for a brief moment in the same way that you "defy gravity" in that brief moment cresting the peak of a roller coaster. That transitional period period, where one dominant force is replaced by another. Please forgive me making up my own physics terms on the fly, but I don't have time to google and sound educated.

When you approach the crest of a roller coaster, the dominant force is the inertia in the upward direction. Then the dominant force becomes gravity. But in the time it takes for those two forces to pass the baton, you're just sort of "forgotten" by physics.

For the slinky, replace upward inertia with spring tension. Which, if I'm not mistaken, is still inertia. "Potential" inertia? As opposed to "kinetic" inertia? I'm probably taking way too many liberties here; if someone else can say this in a way that sounds less stoopid, I'll gladly accept the correction.

I'm sure there is no actual non-binary "transition time between forces" and physics absolutely never "forgets" about you (or a slinky). That has to be nothing more than a nuance of human perception. Like when does a RC time constant graph reach steady state? Can you identify it with your human eye and point to it with your human finger? But that human perception sure is strong. You feel weightless at the top of a roller coaster for good second or so, but I'm sure in reality you weigh a few ounces on either side of zero. And that slink was probably falling imperceptibly at the bottom in the video.

Now I want to see the lead slinky demo.

 

I want to see the slinky demo at different G levels. Does it behave the same on the moon? I mean, without digging through the math (and maybe it was addressed in the video, TLDR), the way the bottom doesn't move seems like a fluke. But maybe not. I get that the top heads down faster than normal, but the bottom remaining stationary is ... odd.