Required force for sphere start rolling

Click For Summary
The discussion centers on the force required to initiate rolling motion in a sphere compared to a cube on the same surface. It is established that the force needed to slide the cube equals the static friction force, μs⋅m⋅g. For the sphere, the required force to start rolling is theorized to be less than this static friction force, as it also involves rolling resistance. The conversation emphasizes the importance of considering torques at the point of contact with the surface to determine the applied force necessary for rolling. Understanding these dynamics is crucial for accurately calculating the forces involved in rolling motion.
eyeweyew
Messages
35
Reaction score
6
Homework Statement
What is the required applied force to the center of mass of the sphere for it to start rolling on a surface?
Relevant Equations
μ[SUB]s[/SUB]⋅m⋅g
Assume there are two objects on the same surface, one is a cube and the other is a sphere. Both objects have the same mass m. The required applied force to the center of mass of the cube for it to start sliding should be equal to static friction force: μs⋅m⋅g.

But what is the required applied force to the center of mass of the sphere for it to start rolling? I assume it should be less than static friction force: μs⋅m⋅g?
 
Physics news on Phys.org
This depends on rolling resistance, not friction (apart from that friction needs to be large enough for the ball to roll rather than slide).
 
eyeweyew said:
But what is the required applied force to the center of mass of the sphere for it to start rolling? I assume it should be less than static friction force: μs⋅m⋅g?
Consider torques about the point of contact with the surface. What torques are there?
 

Thread 'Coulomb's force vs the Lorentz force'

Beams of electrons and protons move parallel to each other in the same direction. They ______. a. attract each other. b. repel each other. c. neither attract nor repel. d. the force of attraction or repulsion depends upon the speed of the beams. This is a previous-year-question of CBSE Board 2023. The answer key marks (b) as the right option. I want to know why we are ignoring Coulomb's force?
View full post »

Similar threads

How can I determine the instant the block overcomes static friction?
2
Replies
61
Views
3K
Why is the direction of kinetic/static friction up a ramp?
Replies
7
Views
1K
Wooden sphere rolling on a double metal track
2
Replies
97
Views
5K
Direction of friction on rolling object
Replies
30
Views
4K
Acceleration of system related to rolling motion and pulley
Replies
35
Views
4K
How can we model a rolling truck on an incline using rotational motion analysis?
Replies
24
Views
2K
Rolling without slipping problem
Replies
42
Views
3K
Question regarding Rolling with and without Slipping and Sliding
Replies
4
Views
2K
Induced charge on a conducting sphere sliced by a plane
Replies
2
Views
1K
What is the relationship between torque, linear force, and rolling resistance?
Replies
13
Views
2K