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

It appears that the subscript is not working properly, please take m1 to means mass 1 and m2 to mean mass2

Atwood's machine consists of two masses connected by a string that passes over a pulley, as show in the figure. Consider the pulley to be massless and frictionless. Show that, if released for rest, m2 takes a time t=[tex]\sqrt{}2h(m2+m1)/g(m2+m1)[/tex] to reach the floor.

[PLAIN]http://rawrspace.com/atwood.jpg [Broken]

2. Relevant equations

I believe,

T-m1g=m1a

m2g-T=m2a

3. The attempt at a solution

So from the relevant equations I solve for T and set them equal. I get

m1a+m1g=m2g-m2a

I solved the equation so that the a's were on one side and the g's were on the other and factored.

a(m2+m1)=g(m2-m1)

Then I divided both sides by (m2-m1)

a(m2+m1)/(m2-m1)=g

Now I am kind of close I think but I am not sure where to go. I know that acceleration (a) is the distance travelled over time squared. So would I replace a with h/t^{2}and then solve the equation to get

t=[tex]\sqrt{}h(m2+m1)/g(m2-m1)[/tex]

That is where I have hit a brick wall because they have it as 2h , I know that both masses move h distance, how did that get incorporated in however ? I also know that there is an equation 1/2(g)t^{2}that may be the way it was introduced, but I do not know how to relate them. Any help would be greatly appreciated.

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# Homework Help: Atwood Machine Proof.

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