Q 11-14-040JEE MainJEE Main 2024 (5 Apr, Shift 2)Easy
A sonometer wire of resonating length $90\ \text{cm}$ has a fundamental frequency of $400\ \text{Hz}$ when kept under some tension. The resonating length of the wire with a fundamental frequency of $600\ \text{Hz}$ under the same tension is ______ cm.
Numerical value type. Enter your answer.
Answer: 60
$f = \dfrac{1}{2L}\sqrt{\dfrac{T}{\mu}} \propto \dfrac1L$:
$$L' = 90\times\frac{400}{600} = 60\ \text{cm}$$
Solution by Sreeraj P, M.Sc Physics