Tablecloth and dishes trick - the BMW version

I'm going for it's fake due to the duration that cloth is on the table.
Unless people know if something like teflon (in quantities normally used for lubrication) can me made into a cloth like material.

Commercial polypropylene tablecloth impregnated with anti-stain is about as slick as teflon. Maybe dampen it down a bit too for added lubrication and I can see it happen.

Fake -- all of the stuff on the table seems equally affected by the tablecloth (i.e. not much), but the impulse acting on the objects at the far end is much, much less than the impulse on the objects at the motorcycle end, due to the difference in contact time with the cloth.

I'm going with real. In stop-action, I can see the earlier candlesticks move more than the later ones, consistent with the acceleration of the bike. I suspect that one major difference in the first and second versions of the trick is the acceleration; the first trick reached a top speed and had no where to go from there, while the second one may have avoided some of the static/accelerating friction probs. I suspect (but am no physicist) that a constant rate of pull would have been problematic by the end.

It seems to me like the dishes are all sort of vibrating in place - I guess that could happen? But it looks kind of odd.

Plus the hyper-enthusiastic guys coming in to congratulate the biker are kind of overdoing it; reminds me of the faked giant-waterslide video.

@ who cares, fwiw, Cordura is teflon. stretched very quickly.

@ Anon (#4): If by "earlier candlesticks" you mean the ones at the end farthest from the motorcycle, they should move less, regardless of the acceleration of the bike. The acceleration doesn't matter.

We're assuming a kinetic friction case here, and that F(k) is constant (probably not, but oh well). The objects, while on the tablecloth, experience a change in momentum of F(k) times time -- the longer they are on the table cloth, the greater the momentum gain. For two objects of equal mass (e.g. the wine glasses), this means a greater velocity gain.

So now you've got two wine glasses at opposite ends of the table. The one at the far end is not moving very fast, because the table cloth was away almost immediately. The one at the motorcycle end has had the table cloth acting on it for about 0.7 seconds, by my reckoning (about 18 frames at 25 fps). It has a greater velocity.

Once the table cloth is no longer under an object, the object's forward motion is halted by kinetic friction with the table. We'll assume this is a constant force as well. Constant force means constant acceleration (slowing down in this case), and under these conditions an object will travel a distance of (speed squared)x(mass)/(2F). So the distance travelled gets larger as the square of the speed.

Bottom line, you should see a much larger separation of objects at the motorcycle end of the table than at the far end. This is not evident in the video.

Or, you can play with the trick yourself (just the small table version) -- you will easily convince yourself that anything that is under the moving table cloth for as much as 0.7 seconds is not going to stay in the same place!

Sorry, one last thing. Not only is it fake, but I'm going to suggest that the entire sequence of the tablecloth being pulled by the motorcycle is CGI -- in several early frames, they didn't quite get it right and it looks like the bystander is in the middle of the table cloth. Hard to describe without a screen shot, but the far edge of the cloth is behind the bystander, with his body breaking the line.

fake-ish. #3 is right, everything seems similarly affected. I think there was a layer of glass or something clear on top of the tablecloth but under the dishes.

Why are people saying the stuff on the table moves? It doesn't move along the table at all, just kind of vibrates in place, like Josh above said.

Just keep your eye on the first candlestick, noting how it lines up with the window frame behind it, you'll see that nothing moves along the table at all.

Ask yourself, what would be easier, faking it with the usual FX magic, or actually getting a motorcycle to accelerate more or less instantly to the speed required, especially on a smooth concrete floor?
Bit of a no-brainer really...

Have you guys heard of camera tricks? A shot of vibrating dishes is superimposed on the tablecloth-pulling shot.

The waste of resources on this debate is very high, while the veracity can be determined by summing up the weight (down force) of the objects above.

This video is fake, towards the end of the tablecloth coming off the cloth flips up under the stuff on the table showing the material on top was super-imposed over the cloth. You may suspect that this is from the edge flicking up, however sides would flick out, not up, the top would however flick up. Basically they have used a reasonably heavy cloth on an empty table then placed an image of wobbly tableware on the top.
The cloth coming off also shows a table with a white surface as the cloth comes off, however the shot showing the table later shows a wood surface.
The makers of this shot should have made sure to have a white table rather than a brown one, a well as hiding weights in the corners of the tablecloth, then they would have not made these errors.

Its fake, if you hit pause when the bike first takes off and the cloth flies up, the onlooker is standing inside the table cloth, then at the end of the cloth you can see the onlookers legs through the cloth, but that is all you can see, nothing else.

The "real" cloth pull contains no silverware or empty plates for a reason, too light and too much surface contact, which means they would move more than the heavier "small footprint" items. Utensils and plates certainly wouldn't remain static on that long table, especially at the pulling-off end. When they pan over the clothless table, even the lightest weight items are in their original postions. Fail.

I've never tried the original, but I can think of several ways to encourage success.

First, the bike has plenty of power to overcome anything put behind it.

Second, slick fabric in industrial quantities is not going to be a challenge to get a hold of. I have a breathable rain jacket next to me that is slicker than snot and it was likely cut from a bolt about 2 meters wide and several hundred long. Mine's blue, but white should not be a problem. If it comes to this, Teflon or PTFE is just another polymer, it comes in everything from various grades of powder for sintering to pipes used for carrying hydrofluoric acid with all different polymer chain sizes. Why somebody wouldn't make a fabric like with nylon and kevlar that had a bit more toughness than plumber's tape is beyond me. Short version, slick fabric that looks like a tablecloth is doable on a commercial's budget.

The real cheat I see is the setup compared with the manual version. The bike has essentially unlimited power and acceleration, to pull off the rip. But look, the things that are likely to fall over and break(the wine goblets) are surrounded by busloads of stuff that is heavy with a low center of gravity. Plates, candlesticks(designed not to topple and set fire to the tabletop, remember)saucers, serving trays, flower arrangements, even teacups and wine bottles in ice buckets and not, take up space and limit the amount of relative motion of the more precarious stuff and also act as a brake against the tabletop once the tablecloth is past. Remember, if you hooked up that 200HP, 650lb bike to the legs of the table instead, the main difference would be a guaranteed mess.

I don't see it so much as a physics impossibility as a confidence scam.

"OMG, look at all that stuff!!11!!11!!"

"Yes, exactly." ;~)

Obvious use of green screen for the table or cloth when watching. Ask some videography guys.

FYI, Mythbusters just tested this - busted. Not even with a 100mph run and 600 feet of head start.