Solving a Homework Problem with Mass, String, and Friction

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SUMMARY

The discussion centers on a physics homework problem involving two blocks of mass m_{A} and m_{B} connected by an ideal string, where block A descends at a constant speed with no friction. The participants analyze the forces acting on the blocks using Newton's laws and trigonometry. The consensus is that the correct answer to the problem is the first option, as the relationship derived from the forces indicates that 1/sqrt(3) falls between 0.25 and 0.6, confirming the solution.

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SqueeSpleen
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Homework Statement


There's two blocks of mass m_{A} and m_{B} which are linked by an ideal string. The block of mass A descends at constant speed. There's no friction. If the pulley is ideal, which one of the following is true[/B]
upload_2017-5-19_0-33-15.png

Homework Equations


Newton laws and trigonometry I think.[/B]

The Attempt at a Solution


I think that the correct answer is the second one, but the first one is marked as correct so I wanted a second opinion.
My reasoning is the following: If the speed is constant it means there is no acceleration, so the sum of the forces is 0. Then I decomposed gravity in the component that's compensated by the normal force done by the triangle and it's perpendicular component. So I arrived to
m_{A} (1/2) = m_{B} sqrt(3)/2
Now that I check, it isn't item 2. it would fall in item 1 as 1/sqrt(3) is between 0.25 and 0.6
Right?

sorry for the typos, I broke my keyboard yesterday (I won't drink coffee while on computer again) and I'm with a rubber one until a new one arrives, at least it's better thanthe one that windows have to use with the mouse.

[/B]
 

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Working it out very quickly, and thus prone to error, I think the first answer is correct.
 
SqueeSpleen said:
it would fall in item 1 as 1/sqrt(3) is between 0.25 and 0.6
Right?
Yes.
 
Absolutely correct! Way of solving by simply taking their Sine components of 'g' and solve it.
 

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