Wave speed on a string of non-uniform linear mass density

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SUMMARY

The discussion focuses on determining the wave speed on a string with non-uniform linear mass density, specifically a chain suspended from a ceiling. The wave speed is derived from the equation V = √(F/μ), where F is the tension due to the weight of the string and μ is the linear mass density. The tension varies along the string, leading to a wave speed that is a function of the height x. The participant attempts to relate the wave speed to the position on the string but encounters difficulties in expressing this relationship accurately.

PREREQUISITES
  • Understanding of wave mechanics and wave speed equations
  • Familiarity with linear mass density (μ) and its calculation
  • Knowledge of tension in strings and its dependence on mass and gravity
  • Basic calculus for relating wave functions to position
NEXT STEPS
  • Research the derivation of wave speed in non-uniform strings
  • Study the relationship between tension and height in suspended chains
  • Explore the application of the wave equation in varying media
  • Learn about the effects of linear mass density on wave propagation
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Students studying physics, particularly those focusing on wave mechanics, as well as educators and researchers interested in the dynamics of non-uniform strings and wave propagation in varying mass densities.

JohnLCC517
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Homework Statement


[/B]
Consider a long chain of mass m and length L suspended from a tall ceiling. Like any string if one end is disturbed waves will travel along the string. However, the tension in the string is due to its own weight and is not uniform. As such the speed of the wave will be different at each point of the string. Determine the speed of the wave as a function of a location of the wave on the string.

Homework Equations


[/B]
Force (F) = mg, Linear mass density (μ) = m/L, Wave Speed (V) = √(F/μ)

The Attempt at a Solution



I began this problem by relating the three relevant equations above as follows;
Wave Speed (V) = √((mg)/(m/l)) = √(g/l), however, I am now stuck on how to relate this as a function of the location of the wave on the string. My initial thought would be to relate this to the velocity of a particle on a string in the following fashion but even this seemed off √(g/l) = -ω A sin (kx - ωt + φ0)
 
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Let's say you call the bottom of the chain x = 0, so that x relates to the height. μ should be a constant, mass per unit length of the chain.
Your tension (F) on the chain at height x: F(x) = x μ g .
I think the position of the wave on the string is just referring to the position x.
 

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