Discontinuity Waves: Deriving the expressions

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SUMMARY

The discussion focuses on deriving expressions for incident, transmitted, and reflected waves when a transverse sinusoidal wave travels along a string with varying linear mass densities (μ1 = 1.0 gr/cm and μ2 = 4.0 gr/cm). The wave is characterized by an amplitude (Ai = 3.0 cm) and a wavelength (λ = 25 cm). Key equations include the wave function y(x,t) = A sin(kx - ωt) and wave speed v = √(T/μ). The challenge lies in determining the amplitude ratios and wave constants at the junction of the two strings.

PREREQUISITES
  • Understanding of wave mechanics and wave equations
  • Familiarity with linear mass density and its impact on wave speed
  • Knowledge of boundary conditions in wave propagation
  • Ability to manipulate trigonometric functions and sinusoidal wave equations
NEXT STEPS
  • Study the derivation of wave equations for strings with different linear mass densities
  • Learn about boundary conditions and their effects on wave transmission and reflection
  • Explore the concept of wave impedance and its role in wave interactions
  • Investigate the mathematical techniques for solving wave equations in piecewise media
USEFUL FOR

Students and educators in physics, particularly those focusing on wave mechanics, as well as engineers working with wave propagation in materials with varying densities.

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Homework Statement




A long string of linear mass density [itex]μ_1 = 1.0 gr/cm[/itex] is joined to a long string of linear mass density [itex]μ_2 = 4.0 gr/cm[/itex] and the combination is held under constant tension. A transverse sinusoidal wave of amplitude [itex]A _i = 3.0 cm[/itex] and wavelength [itex]λ =25 cm[/itex] is launched along the lighter string.


Q. Derive the expressions for the incident, transmitted and reflected waves.


Homework Equations



[tex]y (x,t) = A \sin(k x -\omega t)[/tex]

[tex]v = \sqrt {\frac {T}{μ}}[/tex]

The Attempt at a Solution



Is there a way to derive the expressions mathematically? I know the reflected wave will have the same constant K as the incident wave but will be traveling to the left rather than the right and the transmitted wave will have a different k value than the incident wave but will be traveling to the left.

This is as far as I have gotten with the problem as I can write the expressions from them conclusions but not giving an expression for the amplitudes of the transmitted and reflected waves in terms of the incident wave or waves for the k constants.
 
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You are clearly expected, in this problem, to be able to find formulas for a wave on a string with constant density. Do that for each string, separately, the determine the conditions where the two strings meet.
 

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