A one metre long (both ends open) organ pipe is kept in a gas that has double the density of air at $STP$. Assuming the speed of sound in air at $STP$ is $300\; \mathrm{m} / \mathrm{s}$, the frequency difference between the fundamental and second harmonic of this pipe is ___ $\mathrm{Hz}$
JEE MAIN 2020, Diffcult
Download our app for free and get startedPlay store
$v_{s}=\sqrt{\frac{\gamma P}{\rho}}$

$\frac{\mathrm{v}_{\mathrm{gas}}}{\mathrm{v}_{\mathrm{air}}}=\sqrt{\frac{\rho_{\mathrm{air}}}{\rho_{\mathrm{gas}}}}$

$\Rightarrow \frac{\mathrm{v}_{\mathrm{gas}}}{300}=\frac{1}{\sqrt{2}}$

$\Rightarrow \mathrm{v}_{\mathrm{gas}}=\frac{300}{\sqrt{2}}$

$\therefore \mathrm{v}_{\mathrm{grs}}=150 \sqrt{2}$

Now $\mathrm{n}_{2}-\mathrm{n}_{1}=\frac{\mathrm{v}_{\mathrm{gss}}}{2 \ell}=\frac{150 \sqrt{2}}{2(1)}=75 \sqrt{2}$

$\Rightarrow \Delta \mathrm{n}=106.06 \mathrm{Hz}$

art

Download our app
and get started for free

Experience the future of education. Simply download our apps or reach out to us for more information. Let's shape the future of learning together!No signup needed.*

Similar Questions

  • 1
    If at same temperature and pressure, the densities for two diatomic gases are respectively ${d_1}$ and ${d_2}$, then the ratio of velocities of sound in these gases will be
    View Solution
  • 2
    A transverse wave propagating along $x-$ axis is represented by $y (x,t)= 8.0 sin$ $\left( {0.5\pi x - 4\pi t - \frac{\pi }{4}} \right)$ where $x$ is in metres and $t$ is in seconds. The speed of the wave is ..... $m/s$
    View Solution
  • 3
    The fundamental frequency of vibration of a string stretched between two rigid support is $50\,Hz$. The mass of the string is $18\,g$ and its linear mass density is $20\,g / m$. The speed of the transverse waves so produced in the string is $..........\,ms ^{-1}$
    View Solution
  • 4
    An open pipe of length $33\, cm$ resonates to a frequency of $1000\,Hz$. The mode of   vibration is: (velocity of sound $= 330\, m/s$)
    View Solution
  • 5
    Sound wave travels with a velocity of $300\, m\, s^{-1}$ through a gas. $9\, beats$ are produced in $3\, s$ when two waves pass through it simultaneously. If one of the waves has $2\, m$ wavelength, the wavelength of the other wave is ..... $m$
    View Solution
  • 6
    A composition string is made up by joining two strings of different masses per unit length $\rightarrow \mu$ and $4\mu$ . The composite string is under the same tension. A transverse wave pulse $: Y = (6 mm) \,\,sin\,\,(5t + 40x),$ where $‘t’$ is in seconds and $‘x’$ in meters, is sent along the lighter string towards the joint, the percentage of power transmitted to the heavier string through the joint is approximately ..... $\%$
    View Solution
  • 7
    The rope shown at an instant is carrying a wave travelling towards right, created by a source vibrating at a frequency $n$. Consider the following statements

    $I.$ The speed of the wave is $4n \times ab$

    $II.$ The medium at $a$ will be in the same phase as $d$ after $\frac{4}{{3n}}s$

    $III.$ The phase difference between $b$ and $e$ is $\frac{{3\pi }}{2}$

    Which of these statements are correct

    View Solution
  • 8
    A tuning fork of frequency $512\, Hz$ makes $4$ beats per second with the vibrating string of a piano. The beat frequency decreases to $2$ beats per sec when the tension in the piano string is slightly increased. The frequency of the piano string before increasing the tension was .... $Hz$
    View Solution
  • 9
    The equation $\overrightarrow {\phi \,} (x,\,t) = \overrightarrow {j\,} \sin \,\left( {\frac{{2\pi }}{\lambda }v\,t} \right)\cos \,\left( {\frac{{2\pi }}{\lambda }x} \right)$ represents
    View Solution
  • 10
    A table is revolving on its axis at $5$ revolutions per second. A sound source of frequency $1000 Hz$ is fixed on the table at $70 cm$ from the axis. The minimum frequency heard by a listener standing at a distance from the table will be  .... $Hz$ (speed of sound $= 352 m/s$)
    View Solution