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Dale
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Torque.Low-Q said:What is the reason why the weight will move upwards?
No. Gravity cannot cause a vertical torque. Remember, torque is always perpendicular to the force, so torque from gravity is always horizontal.Low-Q said:One would think at first glance that the vertical torque is solely caused by the weight and gravity.
Let's say that the system is in front of me with the gyroscope facing directly towards me and spinning counter-clockwise. This is an angular momentum pointing horizontally directly towards me.Low-Q said:Wether the precess wants to be clockwise or counterclockwise perpendicular to the guides wouldn't matter as there is no physical precess present due to the guides, right?
If horizontal precess really is an important factor of which vertical direction the weight will move in this system, I will accept that - but have trouble in understanding why.
The weight will cause a torque to the right so the gyro will want to precess to the right. Instead it will run into the guide which will prevent any precession to the right.
The force that the guide exerts will in turn make a torque vertically down. Since the guides allow motion down the gyroscope will precess downwards.
Once it reaches the bottom there will be no more torque due to gravity and therefore no more force from the guide and therefore no more torque from the guide and it will stop precessing.
Why don't you try the analysis if the gyro is spinning clockwise (angular momentum directly away), and see if it precesses up or down. I don't actually know.
Yes.Low-Q said:instead of generating heat, the spinning weight must slow down. Energy must be conserved.
Obviously this is incorrect: energy is conserved. I have dealt with this question multiple times already and am not interested in repeating it yet again over and over. Please re-read my previous comments, if they are not sufficient then go get a textbook because apparently my communication style is not clear enough.Low-Q said:So, then I am back to the initial question in this thread. Analyzed the above system, I now put a gear to the weight so the weight is spinning because I push it along the guides. Whould't that mean that I try to accelerate the RPM of the weight at the same time as the shift of the wheel force to stop it's spin? While doing this, the force from my finger is moving a given distance. This will appearently end up with an energy consume from my side that is not going anywhere - not heat, not increased kinetic energy ?