Wave Motion 3 Question 8
8. In a resonance tube experiment to determine the speed of sound in air, a pipe of diameter $5 cm$ is used. The air column in pipe resonates with a tuning fork of frequency $480 Hz$ when the minimum length of the air column is $16 cm$. Find the speed of sound in air at room temperature.
(2003, 2M)
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Answer:
Correct Answer: 8. $336 m / s$
Solution:
- Fundamental frequency, $f=\frac{v}{4(l+0.6 r)}$
$\therefore$ Speed of sound $v=4 f(l+0.6 r)$.
$$ \text { or } \quad \begin{aligned} v & =(4)(480)[(0.16)+(0.6)(0.025)] \\ & =336 m / s \end{aligned} $$
