I Is angular momentum perpendicular to fixed axis of rotation constant?

AI Thread Summary
Angular momentum perpendicular to a fixed axis of rotation is considered constant when torques acting on the system are ignored, assuming sufficient restraints. However, when a rod is hinged and allowed to rotate, the direction of its angular momentum can change at various points during its motion. The discussion raises the question of whether the torques acting perpendicular to the fixed axis also lie within the plane that is perpendicular to that axis. This highlights the complexity of angular momentum behavior in dynamic systems. Understanding these principles is crucial for analyzing rotational motion accurately.
TahirMaqbool
Messages
16
Reaction score
1
TL;DR Summary
Does the component of angular momentum perpendicular to the fixed axis of rotation change in direction or magnitude?
So my book states torques perpendicular to the fixed axis of rotation tend to tilt the axis , however we assume sufficient restraints exist so these torques are simply ignored.
It follows that angular momentum perpendicular to axis remians constant.
(See image )

My question is that if a rod is hinged at one of its ends and allows to rotate, wouldn't angular momentum perpendicular to axis change in direction at each point?
See image below.
 

Attachments

  • IMG_20231228_205312.jpg
    IMG_20231228_205312.jpg
    43.5 KB · Views: 83
  • IMG_20231228_211214.jpg
    IMG_20231228_211214.jpg
    48.3 KB · Views: 92
Physics news on Phys.org
Are those “torques perpendicular to the fixed axis of rotation” also contained in the plane that is “perpendicular to the fixed axis of rotation”?
 

Thread 'Is calling fictitious forces "not real" just about terminology?'

Hi there, im studying nanoscience at the university in Basel. Today I looked at the topic of intertial and non-inertial reference frames and the existence of fictitious forces. I understand that you call forces real in physics if they appear in interplay. Meaning that a force is real when there is the "actio" partner to the "reactio" partner. If this condition is not satisfied the force is not real. I also understand that if you specifically look at non-inertial reference frames you can...
View full post »

Thread 'Derivation of Hamilton's Principle: Questions'

I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...
View full post »

Similar threads

I Conservation of Angular Momentum vs a gyro at the North Pole
Replies
16
Views
1K
I Effects of External Torques on the Angular Momentum of Asymmetric Bodies
Replies
3
Views
2K
I Conservation of angular momentum during collisions
Replies
3
Views
3K
I Rotation about two axes and angular momentum
Replies
3
Views
2K
Torque, angular momentum and a fixed axis-of-symmetry requirement
Replies
1
Views
1K
Ball hits a pivoting rod, what torque changes the angular momentum of the ball?
Replies
14
Views
2K
Conceptual questions about Angular Momentum Conservation and torque
Replies
2
Views
3K
B Impulse and distance from the axis of rotation
Replies
9
Views
2K
Why is there angular acceleration in a non-spinning gyroscope?
Replies
2
Views
1K
B The physics of flywheel launchers (like tennis ball shooters)
2
Replies
60
Views
4K

Hot Threads

Recent Insights

Back
Top