Why Are There Different Formulas for Wave Velocity?

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SUMMARY

The discussion clarifies that there are two distinct formulas for wave velocity: v=λ/T, which is a general formula applicable to all types of waves, and V=√(T/μ), which specifically describes the speed of a transverse wave on a string. The first formula relates wavelength (λ) and time period (T), while the second involves tension (T) and linear mass density (μ). Both formulas are correct but serve different contexts; the first is a universal relation, and the second is specific to transverse waves.

PREREQUISITES
  • Understanding of wave properties, including wavelength and time period.
  • Familiarity with tension and linear mass density in wave mechanics.
  • Basic knowledge of wave motion and types of waves.
  • Concept of relationships in physics, such as those found in electrical circuits.
NEXT STEPS
  • Study the derivation of wave velocity formulas in different contexts.
  • Learn about transverse and longitudinal waves and their characteristics.
  • Explore the relationship between tension and wave speed in strings.
  • Investigate applications of wave velocity in real-world scenarios, such as musical instruments.
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Students of physics, educators teaching wave mechanics, and anyone interested in understanding the principles of wave motion and their applications in various fields.

mooncrater
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Homework Statement


Actually its not a homework problem sort of thing...I was wandering through a book , studying waves then I realized that there were two formula for the same thing ...the velocity of a wave.

Homework Equations


v=λ/T [where λ is the wavelength and T is the time period]
V=√(T/μ) [where T is tension and μ is linear mass density]

The Attempt at a Solution


I don't know...are both of these correct and I am relating two different things ? or both of them are applied at different places ... I just don't get it...help needed...[/B]

Edit: Is it like that velocity of a wave is defined by the second formula and the first formula is just a relation between λ and T where v is a constant .[ Just like in the case of resistance in dc circuits where R=ρl/A actually defines Resistance whereas V=RI is just a realtion between V & I where R is just a constant]
 
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Your first expression is general and does not depend on the type of wave. It is derived essentially from basic wave motion and from how we define the wavelength and period.

The second expression is the speed of a transversal wave on a string. Using both expressions, you could essentially derive a relationship between the period and the wavelength in terms of the tension and the linear mass density for this type of wave.
 
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Okay i got it now. Both of them are correct...It is just that first one is general whereas 2nd one is for the particular case of a transversal wave.
 

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