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

The two masses in the Atwood’s machine shown in Figure 8–23 are initially at rest at the same height. After they are released, the large mass, m2 falls through a height h and hits the floor, and the small mass, m1rises through a height h. Find the speed of the masses just before m2 lands if h = 1.2m, m1 = 3.7kg and m2 = 4.1kg

2. Relevant equations

E=Eo

Ug=mgh

K=(1/2)mv^2

3. The attempt at a solution

m1*g*y +m2*g*y = (1/2)*m1*v^2 + (1/2)*m2*v^2

I factored outed g*y and (1/2)*m*v^2

g*y*(m1 + m2) = (1/2)*(v^2)*(m1 + m2)

I cancelled out (m1 + m2)

g*y = (1/2)*v^2

g*y = (1/2)*v^2

2*g*y = v^2

√(2*g*y) = v

√(2*9.8*1.2) = v

This is apparently wrong:

4.85m/s ≈ v

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# Homework Help: Work, Energy, or Work problem

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