Answer:
1.3 m
Explanation:
The wavelength of a wave generated by the string of a guitar, if the string is free to move, is twice the length of the string, that is:
[tex]\lambda=2L[/tex]
L: length of the string = 650mm
By replacing you calculate the wavelength and obtain:
[tex]\lambda=2(650mm)=1300mm=1.3m[/tex]
hence, the wavelength is 1.3 m