How does tension affect the frequency of a standing wave on a string?

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SUMMARY

The discussion centers on how tension affects the frequency of a standing wave on a string, specifically addressing a problem where the fundamental frequency of a string under tension is 250 Hz. When the tension is doubled, the new frequency is calculated to be 354 Hz. The relevant equation discussed is v = (F/(ρ⋅A))^(1/2), where F represents tension, ρ is the density of the string, and A is the cross-sectional area. This equation illustrates that increased tension leads to an increase in the speed of sound in the string, thereby affecting the frequency.

PREREQUISITES
  • Understanding of wave mechanics
  • Familiarity with the equation v = fλ (wave speed equation)
  • Knowledge of physical properties of materials (density and cross-sectional area)
  • Basic algebra for manipulating equations
NEXT STEPS
  • Research the relationship between tension and wave speed in strings
  • Learn about the derivation of the wave speed equation v = (F/(ρ⋅A))^(1/2)
  • Explore the concept of fundamental frequency in vibrating strings
  • Investigate the effects of varying tension on harmonic frequencies
USEFUL FOR

Students studying physics, particularly those focusing on wave mechanics, as well as educators seeking to explain the principles of tension and frequency in strings.

sushichan
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Homework Statement


A string is held under tension, with both ends fixed, and has a fundamental frequency of 250 Hz. If the tension is doubled, what will the new frequency of the fundamental mode be?

Homework Equations



The Attempt at a Solution


I don't know how tension can affect the equation v=ƒλ. I re-read the chapter twice still couldn't find it.(Ans: 354 Hz)
 
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Hello Sushi, welcome to PF :smile: !

Perhaps you can google "vibrating string" ?
 
According to my physics book, the tension affects the speed of sound in the string.
A useful equation is: v = (F/(ρ⋅A))^(1/2)
where F = tension
ρ = density of string
A = cross section area of string :)
 
Looks good to me ! Even better: it matches what one finds, e.g. here

Hey, wait a minute ! We're supposed to help folks find the answers by themselves, not just dump them on a plate !
 
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BvU said:
Hey, wait a minute ! We're supposed to help folks find the answers by themselves, not just dump them on a plate !

I'm sorry, but my jugment was simply that revealing a, for the asker unknown, equation was a way to help him/her in solving the actual problem.
In my opinion it might be hard to know what to search for without knowing what you look for. And physics is after all about problem solving and not google-searching skills, at least it is for me.

However, I'm sorry and will do my best to avoid helping people like this in the future! :)
 
Alettix said:
According to my physics book, the tension affects the speed of sound in the string.
A useful equation is: v = (F/(ρ⋅A))^(1/2)
where F = tension
ρ = density of string
A = cross section area of string :)
What is the derivation of it?
Simply putting values in a formula is not physics.
Although it is OP duty to ask meaning of an equation,
But interest is developed in young guys when one explains them in a proper way.
 
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Thank you all, I know how to solve it now ^^

It's just funny I don't see this formula in the textbook.
 

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