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    Hi,

    I am currently doing an A2 piece of coursework on standing waves and i was wondering if anyone can explain to me why length, weight and tension affect the frequencies required to produce the first and second Harmonics (individually).

    I know it might be obvious, but we're doing the A2 coursework before the A2 course ( and the teacher demanded our coursework had to be "A2 level" )

    Thanks for any help
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    I'm assuming this if for a wave on a string. The equation for wavespeed is  v = \sqrt{\frac{T}{\rho}}. This comes out of the wave equation for a string under tension which I'm guessing you probably don't need to but it can be worked out by analysing the forces on a segment of the string.

    The fundamental frequency occurs when  \lambda = 2L so from  v=f*\lambda you get  f_1 = \frac{v}{2L} where v depends on mass, length and tension.

    This site goes through the derivation of the wave equation for a string under tension. The main points are to resolve the forces in the horizontal and vertical directions. The string only moves up/down so the horizontal forces balance whereas the vertical forces are responsible for the motion of the string.
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    Greater tension = greater wave speed
    Length determines what wavelength waves will fit
    Not sure what you mean by weight, weight of string? anything other than this will just create tension
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    (Original post by suneilr)
    I'm assuming this if for a wave on a string. The equation for wavespeed is  v = \sqrt{\frac{T}{\rho}}. This comes out of the wave equation for a string under tension which I'm guessing you probably don't need to but it can be worked out by analysing the forces on a segment of the string.

    The fundamental frequency occurs when  \lambda = 2L so from  v=f*\lambda you get  f_1 = \frac{v}{2L} where v depends on mass, length and tension.

    This site goes through the derivation of the wave equation for a string under tension. The main points are to resolve the forces in the horizontal and vertical directions. The string only moves up/down so the horizontal forces balance whereas the vertical forces are responsible for the motion of the string.
    Thanks a lot, HUGE help!
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    (Original post by ojpowermake)
    Thanks a lot, HUGE help!
    Glad to be of help
 
 
 
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