Transmission of mechanical wave on two different ropes

Click For Summary
SUMMARY

The discussion centers on the transmission and reflection of mechanical waves on two infinite ropes with identical linear density (μ = 0.1 kg/m) and tension (T = 100 N). The harmonic wave traveling on rope 1 has an amplitude of 3 cm and a frequency of 5 Hz. Key conclusions include that the velocities and wavelengths of the waves remain consistent across both ropes due to equal μ and T. The reflection coefficient is not zero, as the presence of rope 2 alters the force balance at the node, necessitating the application of boundary conditions to accurately determine the amplitudes and powers of the transmitted and reflected waves.

PREREQUISITES
  • Understanding of mechanical wave properties and behaviors
  • Familiarity with wave reflection and transmission coefficients
  • Knowledge of boundary conditions in wave mechanics
  • Basic principles of harmonic motion and wave equations
NEXT STEPS
  • Study the derivation of reflection and transmission coefficients for mechanical waves
  • Learn about boundary conditions in wave mechanics and their applications
  • Explore the mathematical modeling of wave interactions on multiple media
  • Investigate the calculation of average power in wave transmission and reflection scenarios
USEFUL FOR

Students and educators in physics, particularly those focusing on wave mechanics, as well as engineers working with mechanical wave applications in materials science.

Soren4
Messages
127
Reaction score
2

Homework Statement


Two infinite ropes, rope 1 and rope 2, of same linear density ##\mu=0.1 kg/m## have the same tension ##T=100N## and lie on the same plane, one perpendicular to the other. The two ropes are connected in the origin. On one of the two branches of rope 1 an harmonic wave is traveling towards the origin. The oscillation are perpendicular to the plane of the ropes with amplitude ##A=3cm## and frequency ##f=5 Hz##. Determine
a) wavelenghts, frequencies and velocities of transmitted and reflected waves
b) amplitudes of transmitted and reflected waves
c) average power of transmitted and reflected waves

Homework Equations


Reflection and transmission coefficients for mechanical waves, see here https://cnx.org/contents/IEH5M2Ue@2/Reflection-and-Transmission-of

The Attempt at a Solution


a) Since ##\mu## and ##T## are the same for all rope, the velocities and wavelenghts are all the same for all the waves (frequency would be the same in any case)

The problem is that I cannot really figure out what happens for points b) and c).

What I'm quite sure about is that there is no reflected wave on the branch where the wave is coming from, because the coefficient of reflection is zero, since ##\mu## is the same in all the rope 1. I'm also quite sure that there is a transmitted wave.

But are waves generated on rope 2? If so, how to find aplitudes and powers?
 
  • Like
Likes   Reactions: Delta2
Physics news on Phys.org
Soren4 said:
What I'm quite sure about is that there is no reflected wave on the branch where the wave is coming from, because the coefficient of reflection is zero, since μμ\mu is the same in all the rope 1. I'm also quite sure that there is a transmitted wave.
The reflection coefficient is not going to be zero because the additional ropes are going to affect the transversal force balance in the node. You need to find the proper boundary conditions at the node and use them to determine what is going on.
 

Similar threads

  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
4K
  • · Replies 3 ·
Replies
3
Views
1K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 2 ·
Replies
2
Views
3K
Replies
1
Views
2K