Undergrad Formula for maximum angular frequency and velocity

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The formula Vmax = Wmax x L describes the maximum speed of a pendulum bob, where Wmax represents the maximum angular speed. The equation can be interpreted as Vmax = ωmax x L, with ωmax being the maximum angular speed and L the length of the pendulum. The second equation, Wmax = Wθmax, involves two different definitions of angular speed, with ωmax indicating the rotation rate at the bottom of the swing and ω representing the angular frequency of oscillations. The discussion highlights the confusion arising from the notation and suggests a clearer representation of the relationship between angular speed and deflection angle. Understanding these formulas is essential for analyzing pendulum motion effectively.
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I can't seem to find it anywhere
What does this formula mean ? I can't find it anywhere. Vmax=Wmax x L. And Wmax=Wθmax. It came up in the pendulum chapter. L is string length.
 
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I can imagine that Vmax=Wmax x L is actually ##V_{\text{max}}=\omega_{\text{max}}L## where
##V_{\text{max}}=~## maximum speed of the pendulum bob
##\omega_{\text{max}}=~## maximum angular speed of the pendulum relative to the point of support
##L=~## the length of the pendulum.

I cannot imagine what Wmax=Wθmax could be.
 
MenchiKatsu said:
And Wmax=Wθmax. It came up in the pendulum chapter. L is string length.
$$\omega_\text{max} = \omega \theta_\text{max}$$I will make a guess at this one. The notation is confusing because there are two different omegas (##\omega##) being considered here.

On the left hand side of the equality we have ##\omega_\text{max}## which is the rotation rate (in radians per unit of time) for the pendulum at the bottom of its swing.

On the right hand side of the equality we have ##\omega## which is the angular frequency of the oscillations of the pendulum.

Finally we have ##\theta_\text{max}## which is the maximum deflection angle of the pendulum from the vertical.

For instance...

If we have a one meter pendulum under earth gravity, its period is about two seconds. This is an angular frequency (##\omega##) of about ##2 \pi## radians per ##2## seconds. Or about one radian per second.

If this pendulum is launched from rest at a deflection angle (##\theta_\text{max}##) of ##0.1## radians from the vertical, the equation asserts that the rotation rate (##\omega_\text{max}##) of the pendulum at the bottom of its arc will be ##0.1## radians per second.
 
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jbriggs444 said:
I will make a guess at this one. The notation is confusing because there are two different omegas (ω) being considered here.
I agree. It should be something like $$\omega_{\text{max}}=\theta_{\text{max}}\sqrt{\frac{g}{L}}$$ where ##\omega## is a reserved symbol for the angular speed of the pendulum bob.
 
Topic about reference frames, center of rotation, postion of origin etc Comoving ref. frame is frame that is attached to moving object, does that mean, in that frame translation and rotation of object is zero, because origin and axes(x,y,z) are fixed to object? Is it same if you place origin of frame at object center of mass or at object tail? What type of comoving frame exist? What is lab frame? If we talk about center of rotation do we always need to specified from what frame we observe?

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