Acceleration of System of Objects w/ m1=10kg, m2=20kg

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http://img297.imageshack.us/img297/5664/systemofobjectssq1.jpg"

Homework Statement




Find the acceleration of the system of two masses shown in the figure, given that m1 = 10 kg, m2 = 20 kg, θ = 60o and φ = 30o. Assume that the incline plane is smooth (i.e., there is no friction) and that g = 10 m/s2.


Homework Equations


A: T=m[tex]_{2}[/tex]g*sinθ + m[tex]_{1}[/tex]g*sinφ
B: T[tex]_{1}[/tex]=T[tex]_{2}[/tex]
C: F=ma

The Attempt at a Solution


T[tex]_{total}[/tex]=223.2 using A
-----
F=m[tex]_{2}[/tex]g*sinθ - m[tex]_{1}[/tex]g*sinφ

F=123.21
-----
Using C: a=F/m
a=m[tex]_{2}[/tex]g*sinθ - m[tex]_{1}[/tex]g*sinφ / m[tex]_{1}[/tex] + m[tex]_{2}[/tex]
a= 4.11m/s[tex]^{2}[/tex]



I'm not sure how to approach this one...
I know tension = T[tex]_{1}[/tex]=T[tex]_{2}[/tex]...
Then i get the Force that will be going right since m[tex]_{1}[/tex] < m[tex]_{2}[/tex]
and find the acceleration. I just want someone to see if I understood this right.
I was trying to approach the masses as two different components, but it didn't work that well..
 
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Nanoath said:

Homework Equations


A: T=m[tex]_{2}[/tex]g*sinθ + m[tex]_{1}[/tex]g*sinφ
Where did you get this equation?
B: T[tex]_{1}[/tex]=T[tex]_{2}[/tex]
C: F=ma
These make sense.

Do this: Draw a free body diagram for each mass, showing all forces acting. Then apply Newton's 2nd law (your equation C) to each mass. Combine the two equations to solve for the acceleration.