Newtonian Mechanics and Forces Problem

AI Thread Summary
The discussion revolves around solving a physics problem involving tensions in a system with massless ropes and frictionless pulleys. The user has calculated the acceleration of the system to be 2.613 m/s² and provided values for the tensions in various strings, including T1 at 12.413 N and T4 at 35.93 N. They express confidence in their calculations based on reasonable mass and friction values but seek validation from others. The user acknowledges a correction regarding the equation for T1, confirming it aligns with another participant's input. Overall, the calculations appear consistent and accurate for the given parameters.
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Problem, Work, and Solution: http://img375.imageshack.us/img375/9987/physicsfinal.png (You can zoom in if needed)

Sorry for not using the template, this was done in MS Paint and I didn't want to have to type it all out again... Basically, the problem is to find all tensions (ropes/strings are massless) and the acceleration of the system, all in terms of given masses and frictions. The large rectangles are stationary and the circles are massless, frictionless pulleys.

I'd really appreciate if someone could check over this, I did myself more than once and also with numbers, assuming m1 = 1kg, m2 = 2kg, etc and μ = 0.5, it came out to be...
a = 2.613 m/s^2
T1 = 12.413 N
T2 = 27.438 N
T3 = 5.878 N
T4 = 35.93 N
...which seems right because m3 will actually lessen the tension on T3 but T4 will still have to pull all 5 masses so it's higher. Based on the reasonable masses I used and pretty average friction value, I think my answers are right but I still want to be sure.

Thanks!
 
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Anyone? This is due Monday...
 
Equation for acceleration looks right to me.

For T1 however it should be this in my opinion

m1 a = t1 - m1 g

EDIT: Oh, it's the same as yours. Sorry!
T2 also is fine and so should be the rest.
 
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