Question

In a resonance tube experiment when the tube is filled with water up to a height of $17.0\text{cm}$ from bottom, it resonates with a given tuning fork. When the water level is raised the next resonance with the same tuning fork occurs at a height of $24.5\text{cm}$. If the velocity of sound in air is $330\text{m/s}$, the tuning fork frequency is

• A. $2200\text{Hz}$
• B. $550\text{Hz}$
• C. $1100\text{Hz}$
• D. $3300\text{Hz}$

Answer 1

The correct option is A $2200\text{Hz}$

Given that
$l_1=17\text{cm}$ and
$l_2=24.5\text{cm},V=330\text{m/s},f=?$


$\lambda =2(l_2-l_1)=2\times (24.5-17)=15\text{cm}$

Now, from
$\Rightarrow v=f\lambda \Rightarrow 330=\lambda \times 15\times {10}^{-2}$

$\therefore \lambda =\frac{330}{15}\times 100=\frac{1100\times 100}{5}=2200\text{Hz}$