# System of Objects

1. Sep 23, 2008

### Nanoath

http://img297.imageshack.us/img297/5664/systemofobjectssq1.jpg" [Broken]
1. The problem statement, all variables and given/known data

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.

2. Relevant equations
A: T=m$$_{2}$$g*sinθ + m$$_{1}$$g*sinφ
B: T$$_{1}$$=T$$_{2}$$
C: F=ma

3. The attempt at a solution
T$$_{total}$$=223.2 using A
-----
F=m$$_{2}$$g*sinθ - m$$_{1}$$g*sinφ

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

I'm not sure how to approach this one....
I know tension = T$$_{1}$$=T$$_{2}$$...
Then i get the Force that will be going right since m$$_{1}$$ < m$$_{2}$$
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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Last edited by a moderator: May 3, 2017
2. Sep 24, 2008

### Staff: Mentor

Where did you get this equation?
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.