(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A simple trebuchet is shown in the figure. Model it as a stiff rod of negligible mass, 2.70 m long, joining particles of mass 73.0 kg and 0.100 kg at its ends. It can turn on a frictionless, horizontal axle perpendicular to the rod and 12.0 cm from the large-mass particle. The rod is released from rest in a horizontal orientation.

The trebuchet is something like a seesaw with the pivot (in this case) being closer to the heavier weight.

2. Relevant equations

3. The attempt at a solution

I tried to find the torque, T = 9.8(73*0.12 - 0.1*(2.7-0.12)) = 83.3Nm

I find the Work, W = integrate T wrt to theta with limits from 0 to pi/2 = 131J

v = sqrt(2*131/0.1) = 51.2m/s

I also tried finding the moment of inertia, I = 67.6kgm^{2}

131 = 0.5 * 67.6 * w^{2}

v = r* w = 5.08m/s

My concept for this topic on rotation of rigid object is very weak, so I hope someone can help me out with this question. Thanks

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# Homework Help: Finding the speed of a trebuchet

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