Masses and inclined plane with friction

AI Thread Summary
The discussion centers on calculating the acceleration and tension in a system involving two masses connected by a string, with one mass on a horizontal plane and the other on an inclined plane at a 40-degree angle. The user is struggling to derive the correct equations for both masses, which include the effects of friction. They correctly note that the tension in the string is equal in magnitude for both masses but acts in different directions. The approach involves setting up equations based on Newton's second law, leading to two equations with two unknowns: tension (T) and acceleration (a). The user seeks clarification on solving these equations to find the desired values.
nynja
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Homework Statement


What is the magnitude of the acceleration of the system, and what is the tension on the string.

The setup is there is 2 masses m1 and m2 which are connected by a string. One is on top of a flat horizontal plane, while the other is on an inclined plane with angle 40 degrees.

m1 mass = 2.65kg
m1 static friction = .61
m1 kinetic friction = .47
m2 static friction = .53
m2 kinetic friction = .36
m2 mass = 9. kg


if it matters the picture looks like this

________________
\
\
\
\
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____________________\m2 is on this incline

Homework Equations


F=ma
F=Fg-Fk



The Attempt at a Solution


I have tried to calculate the acceleration for each of the masses but it is not the right answer I am almost absolutely stuck on this problem. Again I want to understand so a push in the right direction would be perfect
 
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Do for each body a diagram of all the forces and have in mind that the force T from string will be equal in magnitude for both bodies (though T will have different direction, for body 1 will be horizontal while for body 2 will be inclined 40degrees).

For body 1 it will be T-.47m_1g=m_1a where a is the acceleration which is common for both bodies.
Find the equation for body 2 and then you ll have two equations with 2 unknowns which are T and a.
 
Thank you for the quick reply :)

So if I understood you correctly the tension for mass 2 is:
T-.36mg sin(40) = m2a

Then do I solve for T in both equations and add them together to get the magnitude?
Same for the acceleration, but if I remember correctly acceleration is the same for the entire system?

Thanks again
 
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