Friction Conundrum: Why Does Wheel Keep Rolling?

  • Thread starter Thread starter Ravnus9
  • Start date Start date
  • Tags Tags
    Friction
Click For Summary

Homework Help Overview

The discussion revolves around the dynamics of a wheel rolling without slipping on a surface, specifically focusing on the role and direction of friction in this scenario.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the relationship between angular velocity and friction, questioning how friction acts when the wheel is rolling without slipping. There are attempts to apply the work-energy theorem and discussions about the direction of friction in relation to motion and angular acceleration.

Discussion Status

The conversation is ongoing, with participants examining different interpretations of the frictional forces at play. Some guidance has been offered regarding the nature of angular velocity and its relation to friction, but no consensus has been reached.

Contextual Notes

Participants express uncertainty about the fundamental principles of friction and angular motion, indicating a need for further clarification on these concepts.

Ravnus9
Messages
8
Reaction score
0
You have a wheel that is rolling without slipping on the ground, it is being subjected to no outside tourque or pulling force... which way is friction acting and why.
I thought that this would be easy but it turns out to be tricky, if the wheel isn't slipping the velocity equals omega times the radius, and you solve and get a direction of the friction... using work kenetic energy theorem... but that direction always seems to be in the opposite direction itd have to be according to the angular velocity, can anyone help?
 
Physics news on Phys.org
Friction always (I'm not 100% sure on this though) opposes motion. If a wheel is rolling right, the part of the wheel making contact with the ground is moving left so the friction vector is pointing to the right.
 
Ok yeah but then the angular acceleration is to the left because the wheel is slowing down... which means that friction should be is the opposite direction right? but angular velcocity should agree with the direction of friction... which means you have two frictions opposing each other
 
Last edited:
Why are you saying that the angular velocity should agree with the direction of friction? The direction of the angular velocity vector for a wheel is parallel to the axis of rotation. Right?
 
yeah i don't know... you are correct, i think it was one of those things where i was making it harder in my head than it has to be, thanks for your help :)
 

Similar threads

  • · Replies 7 ·
Replies
7
Views
2K
Replies
4
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
24
Views
3K
  • · Replies 42 ·
2
Replies
42
Views
5K
  • · Replies 60 ·
3
Replies
60
Views
5K
  • · Replies 30 ·
2
Replies
30
Views
5K
  • · Replies 12 ·
Replies
12
Views
3K
Replies
13
Views
3K
Replies
1
Views
2K