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**1. Homework Statement**

Two blocks with different mass are attached to either end of a light rope that passes over a light, frictionless pulley that is suspended from the ceiling. The masses are released from rest, and the more massive one starts to descend. After this block has descended a distance 1.30 , its speed is 1.00 .

If the total mass of the two blocks is 18.0 , what is the mass of the more massive block?

Take free fall acceleration to be 9.80 .

I set the heavier block as m1.

**2. Homework Equations**

m1gh1+0.5m1v1^2=m2gh2+0.5m2v2^2

**3. The Attempt at a Solution**

They both start at height 0 and velocity 0 and so the initial PE and KE is going to be 0, and so the initial Mechanical energy is also 0 (I'm pretty sure this is wrong but don't know how to fix it). Then m1 drops 1.30m so thats h1 and m2 goes up -1.30m=h2. v should be equal between both, m1=1, m2=-1.

m1(gh1+0.5v^2)=m2(gh2+0.5v^2)

m1/m2=(gh2+0.5v^2)/(gh1+0.5v^2)

=(9.8*-1.30+1/2*-1^2)/(9.8*1.30+1/2*1^2)

Therefore

m1=-m2

So its wrong ahah I was wondering if someone could help me?

Thanks in advance!:shy: