Question 1 :
Calculate the speed of the wave whose wavelength is 2 m and having a frequency of 220 Hz?
Question 3 : <p>If the velocity of sound in a gas is 360 m/s and the distance between compression and the nearest rarefraction is 1m, then the frequency of sound is</p>
Question 4 :
A man pronounces $a,\space b, \space c, \space d$ and $e$ and hears last four syllables as an echo. Taking velocity of sound as $340\space ms^{-1}$, the distance of reflecting surface, if it takes one-fifth of a second to pronounce or hear one syllable is
Question 6 :
The speed of sound through oxygen gas at T K is $v\ m\ {s}^{-1}$. As the temperature becomes 2T and oxygen gas dissociated into atomic oxygen, the speed of sound:
Question 7 :
A boy stands facing a high wall at a distance of 85 m from it and then blows a whistle. Calculate the time interval when he hears an echo (Speed of sound = 340 m $s^{-1}$).
Question 9 :
Sonar is an instrument used for finding the depth of sea. State true or false.
Question 13 :
769Hz longitudinal wave in air has a speed of 344m/s. How much time is required for the phase to change by 90 degrees at a given point in space?<br>
Question 14 :
Sound waves of wavelength $\lambda$ travelling in a medium with a speed of $v\,\,m\,\,s^{-1}$ enter into another medium where its speed is $2v\,\,m\,\,s^{-1}$. Wavelength of sound waves in the second medium is
Question 15 :
Lightning can be seen the moment it occurs. Paheli observes lightning in her area. She hears the sound 5 s after she observed lightning. How far is she from the place where lightning occurs? (Speed of sound $= 330$ m/s)<br>
Question 16 :
The frequency of a wave is 5 Hz. It refers to (type of wave) ___________.
Question 18 :
A sonar device on a submarine sends out a signal and receives an echo 5 s later. Calculate the speed of sound in water if the distance of the object from the submarine is 3625 m :<br/>
Question 19 :
Which of the following can be used to detect a flaw inside a metal block ?
Question 20 :
The wavelengths of two sound notes in air are $\displaystyle \frac { 40 }{ 195 } m$ and $\displaystyle \frac { 40 }{ 193 } m$. Each note produces $9$ beats per second separately with a third note of fixed frequency. The velocity of sound in air in $m/s$ is:
Question 21 :
Assertion - the basic pf Laplace correction was that, exchange of heat between the region of compression and rarefraction in air is not possible.<br>reason - Air is a bad conductor of heat and velocity of sound in air is large.
Question 22 :
A person is in between two vertical mountains. The person fires a gun then hears the first  echo from the nearby mountain in a time 3s and hears second echo from far mountain in a time 4s. The person hears the third echo after<br/>
Question 23 :
Assuming the speed of sound in air equal to $340 \ ms^{-1}$ and in water equal to $1360 \ ms^{-1}$, find the time taken to travel a distance $1700 \ m$ by sound in air<br/>
Question 24 :
Which of the following statements is/are true in case of waves?<br>
Question 25 :
A man standing between two cliffs hears the first echo of a sound after $2$ seconds and the second echo $2$ seconds after the initial sound. If the speed of sound be $330 m {s}^{-1}$, the distance between the two cliffs should be
Question 26 :
The sound of an explosion on the surface of a lake is heard by a boat man $100m$ away and by a diver $100m$ below the point of explosion. If sound takes time $t$ to reach the boat man, how much time approximately does it take to reach the diver?
Question 27 :
A hall has volume 4x6x10 m$^3$. If the total sound absorption of the hall is 27.2metric sabine and 40 visitors are in the hall and each is equivalent to 0.5metric sabine sound absorption then the reverberation time is<br/><br/>
Question 28 :
A sound signal of 140 vibrations per second has ma wavelength of 3.5 m. What is the speed withwhich the wave travels?
Question 29 :
Surface waves strikes the rock with their crests $160\ m$ apart. The velocity of the wave is $40\ m/s$, The time interval between two crests striking the rock is
Question 30 :
The pitch of sound made by a vibrating wire does not depend on its -
Question 31 :
A ship sends a sonar wave to the sea bed which is flat andmeasured several times over a large area. One day thereflected sound wave takes longer time than in previousmeasurements. The possible reason is :
Question 32 :
Under similar conditions of temperature and pressure, which of the following gases will have the largest velocity of sound.
Question 33 :
The note "Saa" on the Sarod and the Sitar have the same pitch. The property of sound that is most important in distinguishing between the two instruments is <br>
Question 35 :
A string of length $2 \,m$ is fixed at two ends. It is in resonance with a tuning fork of frequency $240 \,Hz$ in its third harmonic. Than speed of sound wave in string and its fundamental frequency is:
Question 36 :
A tuning fork of frequency 328 Hz is moved towards a wall at a speed of 2 ms$^{-1}$. An observer standing on the same side as the fork hears two sounds, one directly from the fork and the other reflected from the wall. No. of beats per second is: <br/>(Velocity of sound in air 330ms$^{-1}$).<br/>
Question 37 :
Compressional wave impulses are sent to the bottom of sea from a ship and the echo is heard after $4\ \text{s}.$ If bulk modulus of water is $2 \times 10^9\ \text{Nm}^{-2}$ and the mean temperature is $4^{\circ}\ \text{C}$, then depth of the sea is
Question 39 :
Sound waves of wavelength $\lambda $ travelling with velocity $v$ in a medium enter into another medium in which their velocity is $4v$. The wavelength in $2^{nd}$ medium is :<br/>
Question 40 :
Two sound waves of wavelengths $1\space m$ and $1.01\space m$ produce $10$ beats in $3$ seconds. Then, the velocity of the sound is
Question 41 :
Which characteristic of a sound helps you to identify your friend by his voice while sitting with others in a dark room?
Question 43 :
A person standing between a pair of tall and wide cliffs claps his hands. He hears the first two echoes at 2 sec and 3 sec respectively. If the speed of sound is 330 m/sec, then
Question 44 :
The sound of frequency less than $20$ hertz is known as
Question 45 :
A car is moving with a speed of $72 {km}/{h}$ towards a hill. Car blows horn at a distance of $1800 m$ from the hill. If echo is heard after $10 s$, the speed of sound (in ${m}/{s}$) is
Question 46 :
A particle performs 20 vibrations in 5 secs. The time period of vibration is
Question 47 :
A human heart on an average beat 72 times a minute. Calculate its frequency
Question 48 :
Arrange the speed of sound in gases $V_g$ , solids $V_s$ and liquids $V_l$ in an ascending order.
Question 49 :
A person bangs on a copper pipe that is part of a large warehouse. The sound can be heard in the pipe $100.0$ meters away in $0.02174$ seconds.<br>If the frequency of the sound is $500.0\ Hz$, what is the wavelength of the second wave in the copper pipe?
