How Do You Solve a Frictionless Pulley System Problem?

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Homework Help Overview

The problem involves a frictionless pulley system with two blocks: one resting on a horizontal surface and the other suspended. The original poster presents a scenario where the tension in the rope is given, and they seek to determine the acceleration of the blocks and the mass of the hanging block.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to solve for the acceleration and mass using the given tension and has shared their calculations. Some participants question the consistency of the direction chosen for the acceleration of the hanging mass.

Discussion Status

The discussion is ongoing, with participants providing feedback on the original poster's approach. There is an emphasis on reviewing the free body diagram and clarifying the direction of acceleration for both blocks.

Contextual Notes

Participants note inconsistencies in the original poster's choice of directions and the axes used in their analysis, which may affect the interpretation of the problem.

Yosty22
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Homework Statement



A light rope is attached to a block with mass 4.00 kg that rests on a frictionless, horizontal surface. The horizontal rope passes over a frictionless, massless pulley, and a block with mass m is suspended from the other end. When the blocks are released, the tension in the rope is 10.0N.
a.What is the acceleration of either block?
c.Find the mass m of the hanging block.

Homework Equations



ƩF=ma

The Attempt at a Solution



My attempt at solving the problem is attached. Can someone tell me where I went wrong?
(It got cut off at the bottom, it just says that my answer of 0.813kg is wrong, but I don't know why. THE CORRECT ANSWER IS: m=1.37kg
 
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Sorry, My attempt at the solution is now attached.
 

Attachments

You've been inconsistent in your choice of directions. Which way is the mass m accelerating?
 
Recheck your free body diagram. Where are the blocks accelerating? Specifically, on what axis as I am seeing two different axis here and that is not correct.

EDIT: Sorry, didn't see haruspex's post when I responded, I did the same problem.
 

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