Calculating Force to Accelerate Mass M Without Moving m1 and m2 - Newton's Laws

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To determine the force required to accelerate mass M without moving masses m1 and m2, it is essential to recognize that all masses must share the same acceleration in the horizontal direction while remaining stationary relative to M. The absence of friction simplifies the problem, allowing the use of Newton's laws to analyze the forces involved. A free body diagram can help visualize the forces acting on each mass, which is crucial for applying Newton's second law. The key is to ensure that the acceleration of M is sufficient to keep m1 and m2 stationary in relation to it. Understanding these principles will lead to the correct calculation of the required force.
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Homework Statement


Hey.. I don't know exactly how to get the solution for this one...

We assume there are no frictions at all and we only look at the masses M, m1 and m2 (rope etc are massless)

I want to know how much force do i have to give to push M in such a way that it accelerates so fast that m1 and m2 won't move related to M?

fahrzeug_223.jpg



Homework Equations



Well... Newton is our friend ;)


The Attempt at a Solution



Maybe [PLAIN]http://img713.imageshack.us/img713/8880/fffpw.jpg ? But I am totally not sure about this...
 
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thoff430 said:

Homework Statement


Hey.. I don't know exactly how to get the solution for this one...

We assume there are no frictions at all and we only look at the masses M, m1 and m2 (rope etc are massless)

I want to know how much force do i have to give to push M in such a way that it accelerates so fast that m1 and m2 won't move related to M?

fahrzeug_223.jpg



Homework Equations



Well... Newton is our friend ;)


The Attempt at a Solution



Maybe [PLAIN]http://img713.imageshack.us/img713/8880/fffpw.jpg ? But I am totally not sure about this...
Neither am I, since I don't know where this equation comes from. Note that since there is no movement of the masses m1 and m2 with respect to M, then all masses must have the same acceleration in the x direction, and no acceleration in the y direction. Draw free body diagrams, identify the forces acting, and use Newton's 3 laws.
 
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