Kinematics of Rigid Bodies question

AI Thread Summary
A uniform 3.6m pole, hinged to a truck bed, is released from a vertical position as the truck accelerates at 0.9m/s². The discussion focuses on calculating the angular velocity of the pole when it reaches a horizontal position, considering both the pole's downward acceleration due to gravity and the truck's acceleration. The relevant equations for angular motion are debated, particularly the use of angular acceleration formulas without a mass value for the pole. It is noted that the pole accelerates left at 0.9m/s² while also experiencing gravitational acceleration downward. The final suggestion involves integrating forces and moments to derive the angular velocity, leading to an approximate value of 3.
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Homework Statement


The uniform 3.6m pole is hinged to the truck bed and released from the vertical position as the truck starts from rest with than acceleration of 0.9m/s^2. If the acceleration remains constant during the motion of the pole, calculate the angular velocity of the pole as it reaches the horizontal position.
Diagram attached.

Homework Equations


I believe these equations are relevant, however, I am not given a mass for the pole, so I'm not entirely sure.
a(tangential)=mrθ''
a(normal) = mrω^2
ƩMo=Iθ''+Ʃma(vector)d
I=k^2m
ω=2Vx
ω=(ωo^2+2aθ)^(1/2)

The Attempt at a Solution


So I eventually want to realize the angular velocity ω.
I have done a similar question that utilised energy and momentum methods, however, with a negligible mass, I'm not sure whether that will affect the equations, since the example question used mass.

So essentially, I believe it may be using the last formula I provided, since it is not determined by time or mass.
So, all I need to find is the acceleration, since I already know that ωo is at rest, and θ=90. Finding the acceleration, from the given positive direction of acceleration of the truck body, is something that I can't figure out.

Thankyou for any feedback!
 

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your last formula is valid for constant angular acceleration,so from vertical to horizontal position does it remain the same.
 
@ Andrien
Well, the pole accelerates to the left (opposite the direction of the car) at 0.9m/s^2, and accelerates downward at 9.8m/s^2.
These are both constants, but I don't know which to use in the formula.
It can't possibly as simple as angular vel=(0^2+2*0.9*90)^1/2
 
consider taking moment about hinge point, and write ma as a pseudo force along with gravity which will act towards left i.e. opposite to acceleration of truck.integrate from 0 to pi/2,you will get
w=[3(g+a)/l]^.5, where l= length of rod.assuming k^2=l^2/12,
w is around 3.
 

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