Kinematics[polar coordinate] concept problem

AI Thread Summary
The discussion focuses on understanding the velocity components of a car in polar coordinates, specifically addressing the relationship between angular velocity (ω) and the radial and vertical components of velocity. The user expresses confusion about the inclusion of the vertical component (h) in the velocity calculations, noting that the car has both horizontal (Vr) and vertical (Vh) velocity components. It is clarified that while the distance to the vertical shift (R) changes, it does not affect the angular component of velocity (V(θ)). The user concludes that the vertical velocity does not contribute to V(θ), emphasizing the distinction between the components in the x-y plane. This highlights the complexities of kinematics in polar coordinates.
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Formula:
http://freep.cn/p.aspx?u=v20__p_0711201059233972_0.jpg

1)I need to find out V(\theta). But I remember that r\theta<dot>
= \omega = V(\theta)

Something seems like contradict
Where my concept wrong?
How should I deal with this problem??
I guess that the h should be included ~but why?
 
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The car has two velocity components. The horizontal component Vr = r*omega. It is given that h = cos(2theta) + 1. Therefore vertical component of the velocity Vh = dh/dt = -2sin(2theta)*d(theta)/dt.
The resultant of Vr and Vh gives the velocity of the car.
 
v(\theta)=\omega R(\theta)

Distance of car to vertical shift is always changing and equals R(\theta)
 
This variation is along the radius and hence it does not affect the theta component of the velocity.
 
But theta is on x-y plane

\omega=\frac{d\theta}{dt}
 
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Distance of car to vertical shift is always changing and equals Rcos(phy) This velocity does not contribute to V(theta)
 
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