Rolling Ball on a Horizontal Bar with Angular Velocity ω

AI Thread Summary
A bar of length L is rotating with angular velocity ω, and a ball of mass m rolls on it without friction, starting with an initial velocity u0. The discussion focuses on the forces acting on the ball, specifically the Coriolis and centrifugal forces, and how to relate the ball's velocity (v) to its position (x) to solve the motion equations. The key equation derived is d²x/dt² = 2ωv, which needs to be connected to find the time when the ball reaches the end of the bar at x = L. Participants emphasize understanding the direction of forces and the ball's movement in a non-inertial reference frame. The conversation highlights the importance of correctly applying physics principles to solve the problem.
m_34n814
Messages
2
Reaction score
0
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!
 
Physics news on Phys.org
We can't help you if you don't show your attempts at the solution.
Please use the homework template provided.
 
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.
 
Last edited by a moderator:
Consider an extremely long and perfectly calibrated scale. A car with a mass of 1000 kg is placed on it, and the scale registers this weight accurately. Now, suppose the car begins to move, reaching very high speeds. Neglecting air resistance and rolling friction, if the car attains, for example, a velocity of 500 km/h, will the scale still indicate a weight corresponding to 1000 kg, or will the measured value decrease as a result of the motion? In a second scenario, imagine a person with a...
Scalar and vector potentials in Coulomb gauge Assume Coulomb gauge so that $$\nabla \cdot \mathbf{A}=0.\tag{1}$$ The scalar potential ##\phi## is described by Poisson's equation $$\nabla^2 \phi = -\frac{\rho}{\varepsilon_0}\tag{2}$$ which has the instantaneous general solution given by $$\phi(\mathbf{r},t)=\frac{1}{4\pi\varepsilon_0}\int \frac{\rho(\mathbf{r}',t)}{|\mathbf{r}-\mathbf{r}'|}d^3r'.\tag{3}$$ In Coulomb gauge the vector potential ##\mathbf{A}## is given by...
Dear all, in an encounter of an infamous claim by Gerlich and Tscheuschner that the Greenhouse effect is inconsistent with the 2nd law of thermodynamics I came to a simple thought experiment which I wanted to share with you to check my understanding and brush up my knowledge. The thought experiment I tried to calculate through is as follows. I have a sphere (1) with radius ##r##, acting like a black body at a temperature of exactly ##T_1 = 500 K##. With Stefan-Boltzmann you can calculate...
Back
Top