Would the friction be in the plane?

  • Context: Undergrad 
  • Thread starter Thread starter Alem2000
  • Start date Start date
  • Tags Tags
    Friction Plane
Click For Summary
SUMMARY

The discussion centers on the interaction between two disks, where the lower disk rotates and the upper disk is dropped onto it. Due to friction, both disks eventually reach the same angular speed, adhering to the principle of conservation of angular momentum. The key point established is that while each disk experiences individual torque, the system as a whole does not experience net torque, allowing for the conservation principle to hold true.

PREREQUISITES
  • Understanding of angular momentum conservation
  • Knowledge of torque and its effects on rotating bodies
  • Familiarity with frictional forces in mechanical systems
  • Basic principles of rotational dynamics
NEXT STEPS
  • Study the principles of torque in rotational dynamics
  • Learn about the conservation of angular momentum in closed systems
  • Explore the effects of friction on rotating objects
  • Investigate real-world applications of rotational motion in engineering
USEFUL FOR

Physics students, mechanical engineers, and anyone interested in the dynamics of rotating systems will benefit from this discussion.

Alem2000
Messages
117
Reaction score
0
If you had two disks with the lower one rotating and dropped the one on top onto it they both come to the same angular speed b/c of friction. How come there is no torqu action on it? Would the friction be in the plane?
 
Physics news on Phys.org
What exactly do you mean when you say "there is no torque action on it?"

If there is friction then eventually the two disks will rotate at the same rate and it will do so in conformance with the principle of angular momentum conservations since there is no net torque on the system of disks. However, and obviously, each disk will experience torque.
 
Okay what I don't understand is ...the conservation of angular momentum requres there to be no net torque...so are you saying that individually there is a torque but not on the system of the two disks?
 
Last edited:
That's exactly what I am saying! :-)
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 19 ·
Replies
19
Views
2K
  • · Replies 41 ·
2
Replies
41
Views
6K
  • · Replies 7 ·
Replies
7
Views
5K
  • · Replies 20 ·
Replies
20
Views
890
  • · Replies 37 ·
2
Replies
37
Views
4K
  • · Replies 4 ·
Replies
4
Views
3K