The sand art is rather pretty. Is this demonstration about explaining the spiral patterns it creates? If so, I think it's because of a combination of rotation along the two axises, with one being "stronger" than the other. When friction (air resistance and movement of the sand) slow the pendulum it starts to settle into an oval. Exponential decay explains why it keeps moving for a long period of time, and has moments that look like its drawing the same shape.
Somebody left t his comment on one of my videos: " In addition, a complete 360 degree precession in a day only occurs at the poles. At the equator, this doesn't occur at all and it's occurrence at various latitudes is proportional to the specific latitude." What do you say? I know of no video that shows no precession anywhere on our flat earth. In other words, the pendulum will always do its thing regardless of where it is on earth, and I have references from 1899.
The video was really good, because it was soothing and intriguing. This leads to some critique, however... - The camera angle was good. I don't think an overhead shot would have been quite as pleasing to the eye, even though it would resolve angular perspective and paradox - as if someone were going to measure what was on the screen to do the math... not, so the angle was good. - The lighting, obviously needs to be mentioned. I realized why you moved it, and thanks for that, but the issue could be resolved from the get go with your set up. A wash screen to diffuse your light source would be good. Or a light box. - The audio with the birds and pendulum mechanics clicking is ideal. Keep it. Don't talk over this. - DO talk about what this is, what you are showing by example, and how it works. An intro perhaps, or maybe redo the part where you show the two straight line diagrams for the two axis of motion. - Perhaps change the pendulum lengths, and make comparison recordings. Thank you for an entertaining video, and good luck with more.
This is really interesting - great video thanks for sharing www.audiobulb.com/create/Lissajous/Lissajous.htm Audiobulb has just released a Lissajous software module. Lissajous is a complex audio/video signal generator built in Max/MSP and inspired by the work of Jules Antoine Lissajous. There is now a wonderful M4L version which works directly with Ableton Live. Users will be able to use Lissajous within their projects, and to midi map all of its parameters. Video and audio outputs all built in. www.audiobulb.com/create/Lissajous/Lissajous.htm
That was remarkably satisfying.
The sand art is rather pretty. Is this demonstration about explaining the spiral patterns it creates? If so, I think it's because of a combination of rotation along the two axises, with one being "stronger" than the other. When friction (air resistance and movement of the sand) slow the pendulum it starts to settle into an oval. Exponential decay explains why it keeps moving for a long period of time, and has moments that look like its drawing the same shape.
Yes, it is combination of two oscillations along the two axes. By "stronger", do you mean "higher frequency"? :-)
+darkblade190 Well, not exactly combination but superposition of SHM.
Lissajous figures are obtained strictly in vector space of eigen-oscillations of a mechanical vibration system
Thank you xmdemo
Does the phase difference change between the two modes of oscillations? I don't think so.
A very good demonstration, my scope can’t even make figures that look that nice
that's a very pretty demo accompanied by some beautiful bird song! what do you feel it teaches your students that they don't get from SHM?
That's BEAUTIFUL!!! Can I ask where on earth is your location?
Singapore. Far away from the edge. Phew.
Somebody left t his comment on one of my videos: " In addition, a complete 360 degree precession in a day only occurs at the poles. At the equator, this doesn't occur at all and it's occurrence at various latitudes is proportional to the specific latitude." What do you say? I know of no video that shows no precession anywhere on our flat earth. In other words, the pendulum will always do its thing regardless of where it is on earth, and I have references from 1899.
learn mechanics of the Foucault pendulum (friction in wires, Coriolis acceleration etc...)
The video was really good, because it was soothing and intriguing.
This leads to some critique, however...
- The camera angle was good. I don't think an overhead shot would have been quite as pleasing to the eye, even though it would resolve angular perspective and paradox - as if someone were going to measure what was on the screen to do the math... not, so the angle was good.
- The lighting, obviously needs to be mentioned. I realized why you moved it, and thanks for that, but the issue could be resolved from the get go with your set up. A wash screen to diffuse your light source would be good. Or a light box.
- The audio with the birds and pendulum mechanics clicking is ideal. Keep it. Don't talk over this.
- DO talk about what this is, what you are showing by example, and how it works. An intro perhaps, or maybe redo the part where you show the two straight line diagrams for the two axis of motion.
- Perhaps change the pendulum lengths, and make comparison recordings.
Thank you for an entertaining video, and good luck with more.
who is joe
I'm not sure Matt, please explain
I recomend not to mix up Lissajous patterns in the sand with Foucault pendulum motion demonstration even they may look alike...!!!
This is really interesting - great video thanks for sharing
www.audiobulb.com/create/Lissajous/Lissajous.htm
Audiobulb has just released a Lissajous software module.
Lissajous is a complex audio/video signal generator built in Max/MSP and inspired by the work of Jules Antoine Lissajous.
There is now a wonderful M4L version which works directly with Ableton Live. Users will be able to use Lissajous within their projects, and to midi map all of its parameters. Video and audio outputs all built in.
www.audiobulb.com/create/Lissajous/Lissajous.htm
IF YOU WANT TO DRAW IN SAND I SAY: DRAW !
shut those birds up