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miamirulz29
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Homework Statement
Three masses connected by light strings are shown in the figure below (I will try my best in describing the figure):
There is light, frictionless pulley with two masses, M2 and M3, on the left and one mass, M1, on the right. They are all connected by light strings. Given m1 = 10 kg, m2 = 7.48 kg, m3 = 8.01 kg, and g = 9.8 m/s2. The acceleration of gravity is 9.8 m/s2 . Find the downward acceleration of m2 mass. answer in units of m/s^2
Homework Equations
SigmaF= ma
mg=fg
The Attempt at a Solution
I drew three separate free body diagrams for each of the masses.
For M1:
Ft-MG=MA
Ft-98=10a
For M2:
MG-Ft=MA
7.48(9.8)-Ft=7.48a
73.304-Ft=7.48a
So I combined the two equations and got -1.413 m/s^2. I though because it is downward, I didn't need the negative, so I put in UT, 1.413, it was wrong, I also put -1.413, it was also wrong. Then I tried using M3 and combined the acceleration of M3 and M2, which was 8.387, which is also wrong. Then I read on another thread that you can use the equation:
A= [(M1-M2)/(M1+M2)] * G. I got 1.413. I honestly don't know what to do at this point, can somebody please help me. Thanks in advance.