Calculating Wave Speed and Wavelength for a Vibrating String

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ddsMom
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Homework Statement



A long string with a mass/length of 500g/m is placed under a tension of 400N. The string is then vibrated up and down with a period of .425sec.

What is the wave speed?

What is the wavelength of the resulting wave?

I have no idea where to beginI would really like to learn this. It's been 20+ years since I have taken a Physics course.
Thank you!


Homework Equations





The Attempt at a Solution



I have no idea where to begin other than this formula:

v=λ/T

I would really like to learn this. It's been 20+ years since I have taken a Physics course.
Thank you!
 
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what resource are you using? (textbook, on-line notes, ??)
...(here are some very brief notes : http://www.science.marshall.edu/foltzc/211t9.htm )

generally to get a speed, you square root a (Force term divided by an inertia density).
tweak the density so that the units come out right for speed.

sqrt[T/(m/L)].
 
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I did use v=sqrt[T/(m/L)]

so I got v=sqrt[400N/(500g/m)] = .029

Am I on the right track?
 
Changed my g to kg. Thank you so so much for confirming.
 
ddsMom said:
I did use v=sqrt[T/(m/L)]

so I got v=sqrt[400N/(500g/m)] = .029

Am I on the right track?

No. You have made error in calculating square root.
 
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right track, but off by a UNITS error ... recall that Newton is composed of kilo-gram, not gram. (N=kg m/s²)
Always include the units that any numerical value multiplies; kg should cancel inside the sqrt.
 
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