Question

Three successive frequencies for a string are 75, 125, 175 Hz. 

(a) State whether the string is fixed at one end or at both ends. 

(b) What is the fundamental frequency? 

(c) To which harmonics do these frequencies corresponds? 

(d) Taking the speed of the transverse wave on the string as 400 m/s, determine the length of the string.

Answer 1

(a) The given harmonics are in the ratio 1 : 3 : 5, so the string is fixed at one end. 

(b) As the common maximum frequency in the harmonics is 25 Hz, so fundamental frequency = 25 Hz. 

(c) The given harmonics are the third, fifth and seventh harmonics.