Why does friction create rolling?

  • Thread starter Thread starter giladbr
  • Start date Start date
  • Tags Tags
    Friction Rolling
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
1 reply · 2K views
giladbr
Messages
2
Reaction score
0
Consider a round object given a push at the middle. The push generates linear velocity, and If there wasn't any friction, the object would start sliding; but the friction in the contact point with the ground causes the object to start rolling.

Intuitively I can explain it: the friction causes the linear speed of the contact point to diminish, and since the other parts of the object still move in the same velocity, rolling is created.

But could somebody provide me with a more thorough physical explanation of what actually happens when the object starts rolling?

Thank you.
 
Physics news on Phys.org
The friction at the edge (surface) applies a moment (force at distance from rotational axis or center of mass) which induces a torque, which induces a change in angular momentum of the mass about the rotational axis.