A 52 cm string resonates at the 7th harmonic. What is the wavelength on the string?

Answer 1

First harmonic wavelength (the fundamental) = 104 cm
Second harmonic wavelength = 52 cm
Third harmonic = 104/3 = 34.67 cm
Seventh harmonic = 104/7 = 14.9 cm

Not to be confused with the wavelength of the sound in air.

Answer 2

Some people call the nth harmonic the nth ABOVE the fundamental and do not call the fundamental a harmonic. In that case, your answer would be 104/8 = 13 cm