I ended up here after reading the description of an old sci-fi movie on Talking pictures, 'The day the earth caught Fire' (1961) I learned about gyroscopic rotation and precession in 'ground school' for aviation, but I'd never heard of Nutation! I've learned something new - amazing!
I've been watching lots of these videos and am s-l-o-w-l-y beginning to understand the effects you describe. I would like to see you give a practical example of calculating procession speed and force so I can understand the units used and such, and to see how accurately the results seem to be reflected in the apparatus being demonstrated.
I had to calculate the exact formulas (ignoring very tiny error terms) in graduate physics class at Temple University many years ago, and then present the exact explanation to the class. While the formulas given here are not exact, they do give a feeling of what is going on. All that is missing is an explanation of why precession and nutation really occur, and this requires more detailed analysis than was done here of the orthogonal rotation produced as the weight attempts to drop due to Earth's gravity field. Ordinary Newtonian mechanics can get very complicated!
@@jiansun7202 That was about 50 years ago. I've certainly forgotten all the details. All I can say is that some textbooks probably do the same analysis I did. Start by considering the experimental apparatus when it is not spinning. Gravity will appear to pull it so it rotates in a particular way. That is the start of the analysis, that rotation due to gravity. It gets much more complex from that point on.
I don't understand it. The formula is counter-intuitive and not fitting the observation. 1. F progression speed is proportional to the R? So if the pole is longer we will have faster progression speed? How can that be? I thought longer pole will cause slower progression. 2. F progression speed is counter-proportional to the rotation speed of the wheel? So when the wheel spin slower we will have faster progression speed? If the wheel spin is closer to 0 then we will have an extremely fast progression speed! How is it possible?
Sorry for the 4-month delay in answering. We don't have good intuition (commonsense physics) for these effects. You have to actually do experiments to see what happens, you can't just guess, like you just did. "Thought experiments" don't work well for understanding precession and nutation until you understand the physics in more detail. There are also more subtle effects in a gyroscope, other than precession and nutation, that are difficult to measure and even less intuitive.
Don't drop it, that is unneeded impact to travel stop. Let it down gently. Also, moving the counter weights towards the mass will tend to balance the devics and give a more desirable presentation.
the earth shape made it tilted at 23.5 cause its not round completely and indeed its closed to an oval shape but not rounded again something close to potato shape. so the center of gravity for the northern sphere and the southern are not match exactly. that cause the earth tilted! the gravity force of the sun considering that 23.5 tilt angle cause the precession.
Now! How to use the math of nutation to predict earth's changing climate. The length of the sign curve from one complete wobble to the next should give us a clue. Then there is the longer sine curve expressed by the precession of the equinoxes. Math experts ought to look at past epochs of sign curve duration to see the future. This would determine the affect pollution has on climate as well; which I think is less than nutation. Climate change is real, but we need to look at the natural components of it to determine our foot print and how severe it actually is.