Rolling Ball on a Horizontal Bar with Angular Velocity ω

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Discussion Overview

The discussion revolves around a physics problem involving a ball rolling on a horizontal bar that is rotating with an angular velocity ω. Participants explore the forces acting on the ball, including Coriolis and centrifugal forces, and seek to establish a relationship between the ball's velocity and its position along the bar.

Discussion Character

  • Exploratory
  • Technical explanation
  • Homework-related
  • Mathematical reasoning

Main Points Raised

  • One participant describes the scenario involving a ball of mass m rolling on a bar of length L, which is rotating with angular velocity ω, and seeks assistance in solving the problem.
  • Another participant emphasizes the need for the original poster to show their attempts at a solution to receive help.
  • A participant introduces the concept of non-inertial reference frames, stating that two forces (Coriolis and centrifugal) act on the ball, and presents a differential equation relating the ball's position and velocity.
  • This participant expresses uncertainty about how to connect the ball's velocity (v) with its position (x) and questions their understanding of the ball's motion.
  • Another participant suggests that the forces acting on the ball are tangential and do not affect radial motion, implying that some forces can be ignored in the analysis.

Areas of Agreement / Disagreement

There is no clear consensus among participants regarding the correct approach to the problem, as some express uncertainty about the forces involved and the ball's motion, while others provide differing perspectives on the relevance of certain forces.

Contextual Notes

Participants have not fully resolved the mathematical relationships or the implications of the forces acting on the ball, leaving some assumptions and dependencies on definitions unaddressed.

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bar (length L) is turned with angular velocity ω, on a horizontal level. Αt length of the bar, there is a ball (mass m) which rolls (We suppose that there is no friction force). The ball begins from constant utmost the bar with initial velocity u0. When the ball reaches in the L?

Can you help me!?
Thank you!
 
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First of all, according to the no Inertial Reference Frame there will be 2 Forces (the once is Coriolis and the other once is Centrifugal).
We can write:
xdx^2/dt^2=-2w*v=-2w*v(z*y)=2w*v*x
or d^2x/dt^2=2*w*v
where v is the velocity of the ball.
I think that I have to write v connection x, and then I can solve this differential equation…
Then I will solve the equation x=L to find t.

My problem is how can I connect v and x.

I think that my problem is the direction of these 2 Forces
In fact, I think that I haven’t understand how the ball will move.
 
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