Mechanics homework confusion

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SUMMARY

The forum discussion revolves around a mechanics homework question involving the creation of right triangles to analyze the forces acting on a block. The main confusion arises from whether to consider the strings as creating two right triangles with sides opposing the block equal to 2 meters or to assume they touch each other within the block. A suggestion is made to consider a triangle with sides 1.25 m, 2 m, and 1.25 m, assuming the strings coincide with the block's center of mass. Additionally, the discussion highlights the importance of clarity in problem statements and suggests revisions for better understanding.

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This discussion is beneficial for students studying mechanics, particularly those struggling with problem interpretation and diagram analysis in physics homework. It is also useful for educators looking to improve clarity in problem statements.

TomPag
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Homework Statement
Mechanics homework
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I have been given the following homework:
?hash=482c827f77e4315baba64b36e91b6eab.webp

For the first question a), I am not sure if i should create 2 right triangles for the strings as drawn in the picture, where the sum of the sides opposing the block are not equal to 2, or if i should say the strings go into the block and touch each other, so that the right triangles created have sides opposing the block equal to 2. If i choose the first option, which makes the most sense, the length 2 m becomes useless, and im not sure how i would solve it. Does anyone have any ideas?
Thank you in advance.
 

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I believe that you can consider a triangle of sides 1.25-2-1.25, assuming that the two strings coincide with the center of mass of the block, and that the opposite ends coincide with the axis of rotation (since there is no given information that contradicts those assumptions).

Diagrams are usually drawn by other than the problem creator, reason for which can be confusing.

562F4D72-6322-4024-9F29-D720480B7D9A.webp
 
TomPag said:
For the first question a), I am not sure if i should create 2 right triangles for the strings as drawn in the picture, where the sum of the sides opposing the block are not equal to 2, or if i should say the strings go into the block and touch each other, so that the right triangles created have sides opposing the block equal to 2. If i choose the first option, which makes the most sense, the length 2 m becomes useless, and im not sure how i would solve it. Does anyone have any ideas?
You could:

a) State that you believe the question posed can’t be answered and briefly explain why.

b) Propose a revision to make answers possible. E.g. replace the 4 kg ‘rectangular’ mass with a 4 kg point mass*.

c) Provide answers based on b).

It may be worth noting that a right-angled triangle with hypotenuse 1.25 m and another side 1.00 m is, in fact, a ‘3-4-5’ triangle.

*Edit: I originally typed '5 kg' but I meant '4 kg'.
 
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