Wave Mechanics Question 737
Question: A string on a musical instrument is 50 cm long and its fundamental frequency is 270 Hz. If the desired frequency of 1000 Hz is to be produced, the required length of the string is
[EAMCET (Engg.) 1998; CPMT 2000; Pb. PET 2001]
Options:
A) 13.5 cm
B) 2.7 cm
C) 5.4 cm
D) 10.3 cm
Show Answer
Answer:
Correct Answer: A
Solution:
$ n\propto \frac{1}{l}\Rightarrow \frac{l _{2}}{l _{1}}=\frac{n _{1}}{n _{2}}\Rightarrow l _{2}=l _{1}( \frac{n _{1}}{n _{2}} ) $
$ =50\times \frac{270}{1000} $
$ =13.5cm $