What Is the Precession Radius of a Spinning Stick with Given Parameters?

Raihan amin
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Homework Statement


A stick of length 2L and of mass M spins with angular velocity ω around the axis perpendicular to the COM of the stick.It is rotating with making an angle Θ,with the axis parallel to Z axis.The COM has an initial velocity v=υ(to the y axis).Find it's precession radius R.

Homework Equations

.
Angular momentom L=IW
Again L=mυR and [/B]
τ=δL/δt

The Attempt at a Solution


I figure out the torque τ and the change of angular momentum .then i find the gyroscopic relationship W=mgr/Iω
Please help me to find the things out.
Thanks.[/B]
 

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Raihan amin said:
A stick of length 2L and of mass M spins with angular velocity ω around the axis perpendicular to the COM of the stick.
Do you really mean to say this? The COM is a point; an axis cannot be perpendicular to it but can only pass through it. It would help if you posted a drawing showing ##\vec \omega## as a straight arrow to clarify the spin axis. Could it be that the spinning stick is to be treated as a spinning top precessing in the Earth's gravitational field? In that case one end must rest on a horizontal plane and the stick must have a non-zero moment of inertia about its axis.
 
kuruman said:
Do you really mean to say this? The COM is a point; an axis cannot be perpendicular to it but can only pass through it. It would help if you posted a drawing showing ##\vec \omega## as a straight arrow to clarify the spin axis. Could it be that the spinning stick is to be treated as a spinning top precessing in the Earth's gravitational field? In that case one end must rest on a horizontal plane and the stick must have a non-zero moment of inertia about its axis.
⇒
Sorry.here the question has some mistake itself.The right version is as follows:
The stick is spinning with angular velocity ω .And the aerodynamic lift coefficient is C. Here gravity should be neglected because the perpendicular part of lift force equate the weight of the stick.
 
And density of air is ρ.
 

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