I had tried in the past with my Dyon top free falling and I had not seen it. But now I tried again and filmed it in slow motion: it flips back and forth! But the flipping is very fast and both sides of the axle have the same color so I didn't realize it was doing it! I'll be out of the house the rest of the day, but I'll make a video when I can.
Last edited by ta0 on Sun Nov 10, 2024 8:27 am, edited 1 time in total.
I wish I had spun the the second video with less wobble, but I didn't want to continue risking the phone in a free fall.
There are 4 inversions in the first part of the video and 6 inversions in the second part. It seems that the frequency of the inversions is more rapid when there is more wobble, which intuitively makes sense to me. Nice video.
"There are 4 inversions in the first part of the video and 6 inversions in the second part. It seems that the frequency of the inversions is more rapid when there is more wobble, which intuitively makes sense to me.".[size=2px]"[/size]
Do you think the starting "speed" is the similar enough for the two runs to be comparable?
In the broader world of tops, nothing's everything! — Jeremy McCreary
ortwin wrote:
Do you think the starting "speed" is the similar enough for the two runs to be comparable?
I am not totally sure. I tried to see the video frame by frame but even so it is difficult to measure the speeds. A mark at the side of the Dyon top would help.
ortwin wrote:
"There are 4 inversions in the first part of the video and 6 inversions in the second part. It seems that the frequency of the inversions is more rapid when there is more wobble, which intuitively makes sense to me.".
Do you think the starting "speed" is the similar enough for the two runs to be comparable?
The starting speed on those two above is similar. But now I recorded a fast and slow start to see the difference it would make: the faster it spins, the faster it flips back and forth:
ta0 wrote:
the faster it spins, the faster it flips back and forth:
I would expect the ratio between the spin frequency and the flip frequency to be relatively constant, at the changing of the spin speed. But my guess is that if there is some wobble, this could lower the ratio, (making the flip frequency faster relatively to the spin frequency).
ta0 wrote:
the faster it spins, the faster it flips back and forth:
I would expect the ratio between the spin frequency and the flip frequency to be relatively constant, at the changing of the spin speed. But my guess is that if there is some wobble, this could lower the ratio, (making the flip frequency faster relatively to the spin frequency).
Yes, that's also my intuition and what the experiments seem to show.
Especially under those conditions -no gravitational force i.e. free fall, no contact to any surface- I find it hard to grasp what is meant by "wobble". Maybe the angle of the initial alignment of the rotation axis relative to a principal axis of the top?
In the broader world of tops, nothing's everything! — Jeremy McCreary
ortwin wrote:
Especially under those conditions -no gravitational force i.e. free fall, no contact to any surface- I find it hard to grasp what is meant by "wobble". Maybe the angle of the initial alignment of the rotation axis relative to a principal axis of the top?
Yes, the angle of the initial alignment of the rotation axis relative to a principal axis of the top.
