Search any question & find its solution
Question:
Answered & Verified by Expert
A tuning fork vibrates with frequency $256 \mathrm{~Hz}$ and gives one best per second with the third normal mode of vibration of an open pipe. What is the length of the pipe? (Speed of sound of air is $340 \mathrm{~ms}^{-1}$ )
Options:
Solution:
2769 Upvotes
Verified Answer
The correct answer is:
$200 \mathrm{~cm}$
$200 \mathrm{~cm}$
According to question, tuning fork gives 1 beat/second with (N) $3^{\text {rd }}$ normal mode. Therefore, organ pipe will have frequency $(256 \pm 1) \mathrm{Hz}$. In open organ pipe, frequency $\mathrm{n}=\frac{\mathrm{NV}}{2 \ell}$
or, $255=\frac{3 \times 340}{2 \times \ell} \Rightarrow \ell=2 \mathrm{~m}=200 \mathrm{~cm}$
or, $255=\frac{3 \times 340}{2 \times \ell} \Rightarrow \ell=2 \mathrm{~m}=200 \mathrm{~cm}$
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.