What Is the Maximum Velocity of a Particle on a Tensioned String?

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Homework Help Overview

The discussion revolves around determining the maximum velocity of a particle on a tensioned string, given specific parameters such as tension, linear density, amplitude, and wavelength of a sinusoidal wave. Participants express uncertainty about how to approach the problem without additional information like frequency or length of the string.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Assumption checking

Approaches and Questions Raised

  • Participants discuss the relationship between tension, linear density, and wave velocity. Some suggest that frequency can be derived from wavelength and velocity. Others question the distinction between the velocity of wave propagation and the maximum velocity of a particle on the string, leading to confusion about the relevant equations.

Discussion Status

The discussion is active, with participants exploring different interpretations of the problem. Some have provided equations related to wave speed and particle motion, while others are questioning the appropriateness of these equations for the specific question posed. There is no explicit consensus on the best approach yet.

Contextual Notes

Participants note the lack of certain information, such as frequency, and express confusion regarding the definitions and relationships between the various parameters involved in the problem.

oldunion
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A string that is under 46.0 N of tension has linear density 5.00 g/m. A sinusoidal wave with amplitude 2.80 cm and wavelength 1.80 m travels along the string.
what is the maximum velocity of a particle on the string.

i don't know how to solve this without a frequency or length of string.
 
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I don't recall the exact relationship, but from density and tension you can find the velocity. Since you have wavelength, you can get the frequency. I'm sure you have the relationship in your text or reference material.

From googling

c = sqrt(T/density per length)
 
wavelength= velocty/frequency.
and i don't understand your reference for density and tension
 
oldunion said:
i don't understand your reference for density and tension

The speed of a wave in a stretched string depends on the tension in the string, and on the mass of the string per unit length (kg/m) which is usually called the linear mass density. Rewriting OlderDan's formula a bit (because I don't like to use [itex]c[/itex] for any speed other than the speed of light, and the linear mass density is usually called [itex]\mu[/itex]):

[tex]v = \sqrt {\frac {T}{\mu}}[/tex]
 
Wait.. isn't this "v" the velocity of propagation? The original question asked for

what is the maximum velocity of a particle on the string.

This is the first derivative of the wave function at zero displacement, no?

Zz.
 
Do you understand that a "particle on the string" is moving up and down, not moving along the string with the wave?
 
[tex]v=\sqrt{\frac{T}{\mu}}[/tex]
[tex]\omega=2\pi \frac{v}{\lambda}[/tex]
[tex]v_{max}=\omega A[/tex]
 
clive said:
[tex]v=\sqrt{\frac{T}{\mu}}[/tex]
[tex]\omega=2\pi \frac{v}{\lambda}[/tex]
[tex]v_{max}=\omega A[/tex]

I understand the equations but why do all of them fit, why not just use the last Vmax to get the answer instead of subbing and letting the end equation be

I don't understand how getting this was the answer

Vmax = (2pi*A)/wavelength * sqrt(Tension/mu)
 

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