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**1. Homework Statement**

A massless beam is supported only at one point, called the pivot point, as shown in the diagram. A block with mass m1 sits at the left end of the beam, a distance L1 from the pivot point. A block with mass m2 sits at the right end of the beam, a distance L2 from the pivot point (L2 > L1). Calculate all torques around the pivot point, remembering that positive is anti-clockwise.

Select Yes, No, Less than, Equal to or Cannot tell.

A. Given particular values of L1 and L2, does the angular acceleration depend only on m1/m2? (If it depends on the actual values of m1 and m2, put no).

B.Given particular values of m1, m2 and L1, is it always possible to choose L2 (with L2 > L1) such that the masses have no angular acceleration?)

C. If m1 = m2, will the masses have an angular acceleration?

D. If m1 L2 = m2 L1, is there a negative torque? (product of mass and distance)

**2. Homework Equations**

**3. The Attempt at a Solution**

I chose for the first one no, as it depends on the values for m1 and m2. The general equation i got for the angular acceleration was:

α = g(m1L1 - m2L2)/(m1L1

^{2}+m2L2

^{2})

On the other hand, I think it's possible to choose an specific value for which the masses will have no angular acceleration (in a way that L2 = (m1L1)/m2). Then, if m1 = m2, the masses will have an angular acceleration as there exists a length difference, so i chose yes for this option. Finally, for the last one, i chose that there is a negative torque (net) as solving for the equation will give us a negative result, so yes.

Could someone please guide me in the right direction? Thank you very much.