Tension T in a parabolic wire at any point

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The discussion revolves around calculating the tension T in a parabolic wire given a load per horizontal foot, w. Participants express confusion over the correct approach, with one noting that following suggestions led to cumbersome terms. A key point raised is the need to correct the equation by replacing y with y2 to reach the target answer. The relevant equations provided include T^2 = T_0^2 + w^2 x^2 and y = (w/2T_0) x^2, which are essential for finding T in terms of x, y, and w. The conversation highlights the importance of careful attention to detail in mathematical problem-solving.
ElectronicTeaCup
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Homework Statement
Assuming that w, the load per horizontal foot, it given, calculate the tension T
Relevant Equations
See (15,16) below
1589367294368.png


I am unsure how to go about this. I tried following the suggestion blindly and end up with with some cumbersome terms that are not the answer. From what I understand the derivative at each point would equal to T?

Answer:
1589367367456.png
I just can seem to get to this. I think I'm there but can't get it in this form

1589367402626.png
 
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ElectronicTeaCup said:
Homework Statement:: Assuming that w, the load per horizontal foot, it given, calculate the tension T
Relevant Equations:: See (15,16) below

View attachment 262705

I am unsure how to go about this. I tried following the suggestion blindly and end up with with some cumbersome terms that are not the answer. From what I understand the derivative at each point would equal to T?

Answer: View attachment 262706 I just can seem to get to this. I think I'm there but can't get it in this form

View attachment 262707
Right at the start you have y on the left instead of y2. Correct that and you should get the target answer.
 
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What's wrong with their suggestion? I assume you got ##T^2 = T_0^2 + w^2 x^2##, and along with ##y =\frac{w}{2T_0} x^2##. That should be sufficient to find ##T## in terms of ##x##, ##y## and ##w##.
 
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haruspex said:
Right at the start you have y on the left instead of y2. Correct that and you should get the target answer.

Yikes! YES, thanks for the catch! I was so frustrated trying to solve this one.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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