Question

In Quincke’s experiment the sound detected is changed from a maximum to a minimum when the sliding tube is moved through a distance of$2.50cm$. Find the frequency of sound if the speed of sound in air is$340m{s}^{-1}$.

Answer 1

Solution:

Step 1: Given information

Speed of sound in air$=340m{s}^{-1}$

The sliding tube is moved through a distance$=2.50cm$

Step 2: Calculate the frequency of sound

Distance between maximum and minimum,

$\Rightarrow \frac{\lambda }{4}=2.50cm$

$$\begin{gathered} \Rightarrow \lambda =2.50x4 \\ \Rightarrow \lambda =10cm \\ \Rightarrow \lambda ={10}^{-1}m \end{gathered}$$

Knows, $v=f\lambda$ or$f=\frac{v}{\lambda }$

$$\begin{gathered} \Rightarrow f=\frac{340}{{10}^{-1}} \\ \Rightarrow f=3400 \\ \Rightarrow f=3.4kHz \end{gathered}$$

Therefore, the frequency of the sound is $3.4kHz$.

Hence, the correct answer is $3.4kHz$.