Velocity of sound in air is

Important Questions on Sound Waves

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A sound wave of frequency $200 \mathrm{Hz}$ is travelling in air. The speed of sound in the air is $340 \mathrm{m} {\mathrm{s}}^{-1}.$ What is the phase difference at a given instant between two points separated by a distance of $85 \mathrm{cm}$ along the direction of propagation?

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A hospital uses an ultrasonic scanner to locate tumors in a tissue. The operating frequency of the scanner is $4.2 \mathrm{MHz}.$ The speed of sound in a tissue is $1.7 \mathrm{km}/\mathrm{s}.$ The wavelength of sound in the tissue is

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Two waves of sound of wavelength $1.2 \mathrm{m}$ and $1.25 \mathrm{m}$ in a medium produce $90$ beats in $10 \mathrm{s}.$ The speed of sound in the medium is

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Sound travels fastest in

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A tunning fork of frequency $480 \mathrm{H}\mathrm{z}$ is used in an experiment for measuring speed of sound $\left(v\right)$ in air by resonance tube method. Resonance is observed to occur at two successive lengths of the air column, $l_1=30\mathrm{c}\mathrm{m}$ and $l_2=70\mathrm{c}\mathrm{m}.$ Then, $\nu$ is equal to:

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A bomb explodes at time $t=0$ in a uniform, isotropic medium of density $\rho$ and releases energy $E$, generating a spherical blast wave. The radius $R$ of this blast wave varies with time $t$ as

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Let the speed of sound at $0 °\mathrm{C}$ be $332{ \mathrm{m} \mathrm{s}}^{-1}$. On a winter day sound travels $342 \mathrm{m}$ in one second. The atmospheric temperature on that day is

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

For a wave, wavelength divided by the time period is equal to_____.

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

The pressure wave, $\mathrm{P}=0.01\sin \left[1000\mathrm{t}-3x\right]\mathrm{N}\mathrm{ }{\mathrm{m}}^{–2}$ , corresponds to the sound produced by a vibrating blade on a day when atmospheric temperature is $0°\mathrm{C}$ . On some other day when temperature is $\mathrm{T}$ , the speed of sound produced by the same blade and at the same frequency is found to be $336\mathrm{ }\mathrm{m}\mathrm{ }{\mathrm{s}}^{–1}$ . Approximate value of $\mathrm{T}$ is:

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Sound waves of wavelength $\lambda$ and velocity $v$ in medium- $1$ enter medium- $2$ . If their velocity in medium- $2$ is $4 v$, the wavelength in medium- $2$ is

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

The velocity of sound in air is independent of change in

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A heavy ball of mass $M$ is suspended from the ceiling of a car by a light string of mass $m \left(m\ll M\right).$ When the car is at rest, the speed of transverse waves in the string is $60 \mathrm{m} {\mathrm{s}}^{-1}$. When the car has acceleration $a$, the wave-speed increases to $60.5 \mathrm{m} {\mathrm{s}}^{-1}$. The value of $a$  in terms of gravitational acceleration $g$ is closed to:

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

When sound travels from air to water the quantity that remains unchanged is

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Consider a gas with molar mass $M.$ If the sound at frequency $f$ is introduced to a tube of this gas at temperature $T$ then an internal acoustic standing wave is set up with nodes separated by $L.$ The adiabatic constant $\left(\gamma =\frac{C_p}{C_v}\right)$ is

HARD

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Sound travels in a mixture of two moles of helium and $n$ moles of hydrogen. If rms speed of gas molecules in the mixture is $\sqrt{2}$ times the speed of sound, then the value of $n$ will be

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A particle is executing SHM along a straight line. Its velocities at distances ${\mathrm{x}}_1$ and ${\mathrm{x}}_2$ from the mean position are ${\mathrm{V}}_1$ and ${\mathrm{V}}_2$ respectively. Its time period is:

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

A particle is executing a simple harmonic motion. Its maximum acceleration is $\mathrm{\alpha }$ and maximum velocity is $\mathrm{\beta }$. Then, its time period of vibration will be:

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

It takes $2.0$ seconds for a sound wave to travel between two fixed points when the day temperature is $10°\mathrm{C}$. If the temperature rises to $30°\mathrm{C}$, the sound wave travels between the same fixed parts in

MEDIUM

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

Consider a system of gas of a diatomic molecule in which the speed of sound at $0^{\mathrm{o}}\mathrm{C}$ is $1260 \mathrm{m} {\mathrm{s}}^{-1}$ . Then, the molecular weight of the gas is in $\mathrm{g} {\mathrm{mol}}^{-1}$, (given, the gas constant $R$ is $8.314\mathrm{ }\mathrm{J} {\mathrm{mol}}^{-1}\mathrm{ }{\mathrm{K}}^{-1}$)

EASY

Physics>Oscillations and Waves>Sound Waves>Speed of Sound in Gases

The percentage increase in the speed of transverse waves produced in a stretched string if the tension is increased by $4\%$, will be ___ $\%$.