Tag: study of sound

Questions Related to study of sound

Which of the following statements is true?

physics study of sound types of waves sound as a wave of disturbance sound waves are longitudinal waves

  1. Pressure undergoes no change at the nodes in the case of longitudinal stationary waves

  2. Pressure is minimum at the nodes in the case of longitudinal stationary waves

  3. Pressure is maximum at nodes in the case of longitudinal stationary waves

  4. None of the above

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Correct Option: C
Explanation:

At nodes in longitudinal waves,there is maximum compression, So, there will be pressure.

Transverse waves can propagate

physics study of sound types of waves sound as a wave of disturbance sound waves are longitudinal waves

  1. only in solid

  2. both in solid and gases

  3. neither in solid nor in gases

  4. only in gases

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Correct Option: A

When source and detector are stationary but the wind is blowing at speed ${ v } _{ w }$, the apparent wavelength ${ \lambda  }'$ on the wind side is related to actual wavelength ${ \lambda  }$ by [take speed of sound in air as v]

physics study of sound types of waves sound as a wave of disturbance sound waves are longitudinal waves

  1. ${ \lambda }'={ \lambda }$

  2. ${ \lambda }'=\frac { { v } _{ w } }{ v } \lambda $

  3. ${ \lambda }'=\frac { { v } _{ w }+v }{ v } \lambda $

  4. ${ \lambda }'=\frac { v }{ v-{ v } _{ w } } \lambda $

Show answer
Correct Option: C

Equation of a longitudinal wave is given as $y=106{-2}\sin 2\pi\left(1000t+\dfrac{50x}{17}\right)$ (all SI units). At $t=0$, change in pressure is maximum (in modulus) at x$=$.

physics study of sound types of waves sound as a wave of disturbance sound waves are longitudinal waves

  1. $0.34$

  2. $0.255$

  3. $0.085$

  4. All of these

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Correct Option: A

Assertion - Sound wave is an example of longitudinal wave.
Reason - In longitudinal waves, the constituents of the medium oscillate perpendicular to the direction of wave propagation.

physics study of sound types of waves sound as a wave of disturbance sound waves are longitudinal waves

  1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion

  2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

  3. Assertion is correct but Reason is incorrect

  4. Both Assertion and Reason are incorrect

Show answer
Correct Option: C
Explanation:

A sound wave is an example of the longitudinal wave.
But in longitudinal waves, the constituents of the medium oscillate parallel to the direction of wave propagation. So sound wave is an example of longitudinal wave.

Which of the following is not a longitudinal wave?

physics study of sound types of waves sound as a wave of disturbance sound waves are longitudinal waves

  1. Seismic P-wave

  2. Light

  3. Sound

  4. Ultrasound

Show answer
Correct Option: B
Explanation:

In case of light, the waveform changes perpendicular to the relative motion. So, it is a type of transverse wave, which causes the medium to vibrate perpendicular to the wave energy .

An echo will be heard if the minimum distance between the source of sound and the obstacle is :

[assume air to be the medium]

physics study of sound conditions for hearing echo echo ultrasound and its applications

  1. $1\;m$

  2. $10\;m$

  3. $15\;m$

  4. $17\;m$

Show answer
Correct Option: D
Explanation:

As the sensation of sound persists in our brain for about 0.1 s, to hear a distinct echo the time interval between the original sound and the reflected one must be at least 0.1 s. If we take the speed of the sound to be 344 m/s at a given temperature, say at 22 $^0 C $ in air, sound must go to the obstacle and reach back the ear of the listener on reflection after 0.1 s. 


Hence, the total distance covered by the sound from the point if generation to
the reflecting surface and back should be at least 

$344 \times 0.1= 34.4 m.$

Thus for hearing distinct echoes, the minimum distance pf the obstacle from 
the source of sound must be half this distance

That is, $\frac{34.4}{2}=17.2\,m \approx 17\,m$

Bats detect the obstacle in their path by receiving the detected

physics study of sound conditions for hearing echo echo ultrasound and its applications

  1. Infrasonic waves

  2. Ultrasonic waves

  3. Both

  4. None

Show answer
Correct Option: B
Explanation:

Bats can produce ultrasonic waves by flapping their wings. They can also detect these waves.these waves produced by the bats after reflection from the obstacles like building guide them to  remain away from the obstacles during night with the help of ultrasonic waves.

The technique used by bats to find their way or to locate food is _______.

physics study of sound conditions for hearing echo echo ultrasound and its applications

  1. SONAR

  2. RADAR

  3. Echolocation

  4. Flapping

Show answer
Correct Option: C
Explanation:

Bats can produce ultrasonic waves by flapping their wings. They can also detect these waves.these waves produced by the bats after reflection from the obstacles like building guide them to  remain away from the obstacles during night with the help of ultrasonic waves.

Voice of which of the following creatures is likely to have maximum frequency ?

physics study of sound conditions for hearing echo echo ultrasound and its applications

  1. Man

  2. Cow

  3. Bird

  4. Dog

Show answer
Correct Option: C
Explanation:

Among the four creatures birds voice has higher pitch than other three. Higher pitch means higher frequency. Pitch determines the shrillness of sound.