How to Solve an Incline Plane and Pulley Problem?

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Homework Help Overview

The discussion revolves around a problem involving an incline plane and a pulley system, where participants are analyzing the forces acting on two masses and their respective accelerations. The subject area includes dynamics and the application of Newton's laws.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants discuss the interpretation of acceleration directions and how they affect the outcomes of the problem. There is an exploration of the reasoning behind different answers based on the chosen positive direction for acceleration.

Discussion Status

The discussion is active, with participants questioning the clarity of the problem statement and offering differing interpretations of the acceleration directions. Some guidance has been provided regarding the validity of choosing different positive directions, but no consensus has been reached on the correct answer.

Contextual Notes

There is mention of potential ambiguity in the wording of the problem, which may lead to different interpretations of the forces and accelerations involved. Participants are also considering the equality of the masses in their analysis.

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Homework Statement


http://img216.imageshack.us/img216/1767/inclineplanevq9.jpg​

Homework Equations


F = ma
sohcahtoa

The Attempt at a Solution


The answer to the question is b, but I got a. I used the sine ratio and divided the forces that were acting on mass 1 by the forces acting on mass 2. Can someone help me on this question?
 
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That's because the question is so badly written. If you consider positive 'a' to be m2 accelerating down, then a) is correct. If you choose positive 'a' to mean m2 is accelerating up, then b) is correct.
 
Actually, if you put it that way, I don't think that the question is worded badly, because m1g would be greater than the parallel force of gravity, so m2 would be accelerating up. Remember, m1 = m2. Can you explain in further detail how you came to your conclusion though?
 
In working these problems, you get to choose which direction you consider positive. You chose a different and equally valid way to do that. The question should have been clearer on that.
 
Last edited:
b) is correct.
 
Can you show me how you got b?
 

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