Waves- sending a pulse across a weighted line

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AI Thread Summary
The discussion revolves around a physics problem involving waves and tension in a weighted line. The original poster expresses confusion about incorporating the weight of blocks into their calculations and determining the force of tension without knowing the angles. Participants suggest that angles can be calculated using trigonometry, which the poster initially overlooked. There is a focus on understanding how to apply various values and variables to solve the problem effectively. Overall, the conversation emphasizes the need for a clearer conceptual framework to integrate the different components of the problem.
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Homework Statement
A light string with a mass of 10.2 g and a length L=3.40 m has its ends tied to two walls that are separated by the distance D=1.85 m. Two objects, each with a mass M=1.83 kg, are suspended from the string, as shown in the figure below.

If a wave pulse is sent from point A, how long (in milliseconds) does it take for it to travel to point B?
Relevant Equations
I was trying to use f=1/2LSqrt(Ftension/u)
or there is also v=sqrt(Ftension/u)

lambda=2L/m

v= f/lambda
1669160664554.png
Here is a picture of the problem:

I honestly am pretty lost, I'm not looking for an answer, more so an idea to get me started. But here is what I was thinking:

In the equation above I was trying to use:
For U I am unsure how to incorporate the weight of the blocks into the u, so I am unsure how to calculate that.

For the Force of tension- I am unsure if you are able to solve for this, as we don’t know any of the angles.

I would then use that to plug into the second equation to find V, then divide that by (L/2) <---the distance.
 
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Couple of comments

Eaoke3 said:
A light string with a mass of 10.210.2 g
That number has too many decimal points
Eaoke3 said:
... we don’t know any of the angles.
Of course you do. A bit of calculation is required, sure, but you DO have them.
 
I corrected it, thank you :- ).

Ohh, well using the L and its corresponding dividing value, I would be able to obtain lengths, but from there I am unsure of how to apply those numbers into anything useful.

I can see that I have different values and variables, but I really think I am missing a big conceptual picture of how to put them all together.
 
Eaoke3 said:
I corrected it, thank you :- ).

Ohh, well using the L and its corresponding dividing value, I would be able to obtain lengths, but from there I am unsure of how to apply those numbers into anything useful.
Can you not see how to use trig to get the angles? I don't know if they are needed to solve the problem but if they are you can get them.
 
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