A very close shave

[Grimer]

Nick, your video was so inspiring I had to try to duplicate it. Here's a video of my attempt: http://www.youtube.com/watch?v=bwCZhoMFoFU

My experiment is a variant of yours. A circular sheet of 1/2" plywood was used and it was balanced (with washers on a bolt) prior to the addition of the two extra masses (m1 and m2). The two extra masses (one tethered and one attached to the plywood) consist of rollerblade wheels with their bearings.
Heights h1 and h2 are referenced to the center of the rollerblade wheels. Height h3 is the height the tethered mass must exceed in order to claim energy gain.

h1 = mass1 at 6 o'clock position: h1 = 0.0 [m]
h2 = mass1 at 12 o'clock position: h2 = 0.543 [m]
h3 = h1 + (2 x h2) + radius of rollerblade wheel = 1.127 [m]
In the experiment, black tape is placed at height h3 for easy verification of energy gain.

m1 = rollerblade wheel 1 = mass attached to plywood: m1 = 0.107 [kg]
m2 = rollerblade wheel 2 = mass attached to the tether: m2 = 0.106 [kg]

mass of the string is less than 1 gram
mass of the plywood with bolts and screws: 1.865 [kg]
mass of the steel plate attaching the plywood to the axel: 1.107 [kg]
mass of axel: 0.279 [kg]

Nick, Unfortunately I was unable to duplicate the results of your experiment. In my experiment, ignoring the mass of the axel, the mass of the "cylinders" part has a total mass of 3.079 [kg], and the mass of the "sphere's" part was 0.106 [kg]. The final potential energy in my experiment was slightly less than 100 percent of the initial potential energy as can be seen by the height that m2 reached relative to the black line.

However, I was able to get the tethered mass m2 to rise above the black line by doubling mass m1 to 0.212 kg. Nick, if there was experimental error in your setup, it could be due to the mass of your lead weight being greater than the mass of your bouncy ball. If they are both exactly 50 grams, then your results are quite interesting.

Nick, I just watched your mad math video. What are you doing to get yours to work?

Loved the music. I used to play it on the pianola when I was a boy.
Not as fast as this girl though:
http://www.youtube.com/watch?v=2Xerxu8mdxQ

Good demo. Nice to see a qualitative confirmation of Nic's video. I hope people appreciate its significance.

[silverfox]

The swing of a hammer more than amply demonstrates that any low-grade mechanical energy input to accelerate the hammer can be readily translated into a very high-grade mechanical energy output on the impact end.

Nic's demo is essentially an elaboration on that particular phenomenon. If any entropy takes places it is quite miniscule compared more ordinary circumstances and why the event appears to be just as dramatic as it is.

Entropy is only a partial description of reality and should in no way be construed as being representative of the whole. Like anything else, it varies directly with the circumstances. If there isn't the time or space for it to develop in any exchange, it won't.

[nicbordeaux]

Mea culpa : I've just disassembled the first wheel, and the weight of the ball is 55 grammes, and the hand fashioned lead weight is 70 odd grammes (looks 72/3, my scales are in 5 gramme increments). How I managed to mess up that badly I don't know. Likely it was when I cut the sheet lead in "half" I took the wrong "half" to make the weight. Not sure how that affects the calculations. And it doesn't explain the second setup which is commercial fishing weight stamped 50g. The second setup did underperform the 1st by about 10%. But there again, it is a totally different wheel.

So, I have made a fool of myself by rushing things and assuming I couldn't be wrong. I apologize to everybody.

I'll now rerun those tests with a proper inplane frame and wheel, check balance points, exact weights (assisted by a second person to verify) , and no doubt the results will be bad. For me.

[beapilot]

Nick,

Please be precises on your second test and make a good video.

Thanks,
Joshua

[ovyyus]

No problem Nick, all good stuff. Thanks for your open and honest enquiry.

Looks like yet another confirmation of CoE. I wonder if people will appreciate its significance?

[Wubbly]

Here are some more tests with m2 positioned in front of or behind m1 in 22.5 degree increments, and also high and low release points. The best case scenario was still output energy less than input energy. :(

In one or two cases the flung mass comes up to the black line, but the insulation panel was sloping back slightly, and the camera is below the level of the black line, so I'm not going to get too excited about it.

(I know I didn't adjust the black line down as the masses were seperated, but the wide seperations turned out to not be the best case scenarios.)

http://www.youtube.com/watch?v=GYmR-2lFtLk

.

[DrWhat]

Brilliant work Wubbly. A true scientist. :(

[beapilot]

Here are some more tests with m2 positioned in front of or behind m1 in 22.5 degree increments, and also high and low release points. The best case scenario was still output energy less than input energy. :(

In one or two cases the flung mass comes up to the black line, but the insulation panel was sloping back slightly, and the camera is below the level of the black line, so I'm not going to get too excited about it.

(I know I didn't adjust the black line down as the masses were seperated, but the wide seperations turned out to not be the best case scenarios.)

http://www.youtube.com/watch?v=GYmR-2lFtLk

.

Wubbly,

I love your creation of videos. Beautiful music pick; lovely. I have been getting similar results with physics software using only bars. I wish I had a wheel to play with; a very sweet adult toy. Great work!

Joshua

[nicbordeaux]

Joshua, you serious ? You can build a wheel setup for free. Angle iron drilled, bike wheel. Or bike hub and plywood or fiberboard discs.

If you need any info, PM and tell me where you live (country), i'll tell you where to get the stuff for zilch.

[nicbordeaux]

EDIT: sorry, removed.