Understanding gyro without angular mom

  • Thread starter Thread starter h0dgey84bc
  • Start date Start date
  • Tags Tags
    Angular Gyro
AI Thread Summary
The discussion focuses on understanding gyroscopic precession using Newton's laws instead of angular momentum and torque. The original poster seeks an intuitive grasp of precession, specifically in the context of a flywheel rotating along the x-axis with gravity acting in the negative z direction. Despite acknowledging the validity of angular momentum explanations, they express a desire to conceptualize the gyroscope's behavior through simple forces. Participants emphasize that angular momentum is essential for a complete understanding, while the poster hints at a composite particle view of the flywheel to explain precession. Ultimately, the conversation highlights the challenge of reconciling intuitive force-based explanations with established physics principles.
h0dgey84bc
Messages
159
Reaction score
0
Hi,

I understand the motion of a gyroscope through considerations of torque and angular momentum, I have no issue with deriving it and imagining it by considering these things, but I somehow feel I still don't understand precession on an intuitive level. I was wondering if anyone could help me understand the motion of a gyroscope without invoking angular momentum/torque, just by soley considering Newton's laws.

Just to avoid confusion, take the z axis as out of the screen, y-axis from bottom to top, x-axis from left to right and I'm considering a flywheel rotating along an axis in the x-direction. Its axial rod is sat on a pivot to the left, gravity is in the negative z direction. Hence torque is in the y-direction, and precession occurs about the z axis.
I've attempted a drawing, that I've attached.

Like I say, I'm happy with the ang mom/torque explanation, I am just looking for a Newtonian one.

Thanks
 

Attachments

  • precession.jpg
    precession.jpg
    6 KB · Views: 371
Physics news on Phys.org
Don't be afraid of angular momentum. You really need it here.
Even Newton used it.
 
clem said:
Don't be afraid of angular momentum. You really need it here.
Even Newton used it.

I'm not afraid of angular momentum, I fully understand the explanation of precession via angular momentum and torque, and no issues with it at all. However I have an itching to understand this via simple forces as well, ultimatley such a picture must be possible here. I think that thinking of the flywheel as a composite object, made up of smaller particles, some of which are moving up, some down, some left some right, etc, when the flywheel spins, is key to understanding why the flywheel precesses when spun, but falls otherwise. Can't quite fully picture it just yet though.
 
I never understood gyroscopes (I still dont) until I read the ping pong ball on a string explanation. as the ball circles around each time it strikes a paddle and glances off at a very slight angle. the result is a downward force on the paddle. you can then easily imagine the effect on the ping pong balls rotation.
 
Thread 'Gauss' law seems to imply instantaneous electric field'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Maxwell’s equations imply the following wave equation for the electric field $$\nabla^2\mathbf{E}-\frac{1}{c^2}\frac{\partial^2\mathbf{E}}{\partial t^2} = \frac{1}{\varepsilon_0}\nabla\rho+\mu_0\frac{\partial\mathbf J}{\partial t}.\tag{1}$$ I wonder if eqn.##(1)## can be split into the following transverse part $$\nabla^2\mathbf{E}_T-\frac{1}{c^2}\frac{\partial^2\mathbf{E}_T}{\partial t^2} = \mu_0\frac{\partial\mathbf{J}_T}{\partial t}\tag{2}$$ and longitudinal part...
Back
Top