Standing waves and vibration frequency

[bigsaucy]

A violinist places her finger so that the vibrating section of a 1.0g/m string has a length of 30cm, then she draws her bow across it. A listener nearby in a 20 degrees celsius room (speed of sound at this temperature in air is 343 m/s) hears a note with a wavelength of 40 cm. What is the tension in the string?


I was having real trouble with this question. I have an exam in 4 hours, any help would be greatly appreciated!

 

[ehild]

The vibration frequency of the string is the same as that of the sound heard in air. The wavelength of the elastic wave in the string is related to the vibrating length of the string. The wavelength is related to the frequency and the speed of the wave. Speed of the wave in the sting is related to tension and density. Put all that together.


ehild