Calculate the Tension and Angular Acceleration in Log After Release

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SUMMARY

The discussion focuses on calculating the initial tension in the cables and the angular acceleration (α) of a uniform 69-lb log used as a battering ram after it is released from rest. The user attempted to solve the problem by summing forces in both x and y directions, leading to equations involving tension (TA and TB) and gravitational force (mg). The user also explored taking moments about the center of the beam but expressed uncertainty regarding the calculation of inertia. The solution requires a clear understanding of static equilibrium and rotational dynamics.

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Homework Statement


The uniform 69-lb log is supported by the two cables and used as a battering ram. If the log is released from rest in the position shown, calculate the initial tension induced in each cable immediately after release and the corresponding angular acceleration α of the cables.


Homework Equations





The Attempt at a Solution



I tried first by summing the forces in the x and y directions

ƩFx: max = TAcos(θ) + TBcos(θ)

ƩFy: may = -mg + TAsin(θ) + TBsin(θ)

I assumed that ax and ay are equal to 0 and then I took these two equations and tried to solve them by using the matrix function on my calculator, but it doesn't work.

I'm now trying to take the moment about the center of the beam

The distances I have used should be the perpendicular distances from the tensions

ƩMG: = Iα = -TA((d+e)/s)sin(θ) + TB((d+e)/2 - d)sin(θ)

but I'm not sure how to calculate the inertia, or if I need to calculate it at all.

Any advice would be greatly appreciated.
 

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I've managed to figure it out using a normal and tangential coordinate system,
 

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