Tag: study of sound

Questions Related to study of sound

sound wave travels from west to east, in which direction do the particles of air move?

  1. west-east

  2. south-north

  3. up-down

  4. none of these


Correct Option: A
Explanation:

Sound waves are longitudinal waves and the particles of the air move in direction of propagation sound. So if the wave will travel in west-east direction,the particles of the air also travels in west-east direction.

Mark the incorrect statement

  1. Sound can be produced by beating an object irrespective of whether there are vibrations or not.

  2. The sound of a tabla normally has a lower pitch than the sound of a violin.

  3. A short flute will produce sound of lower pitch than a long flute.

  4. All


Correct Option: A
Explanation:

(i) False [Sound is produced from a vibrating object.]

(ii) True [The sound of a tabla normally has a lower pitch than the sound of a violin.]

(iii) True[A short flute will produce sound of lower pitch than a long flute.]

Why are the regions of compressions and rare fractions of sound waves formed?

  1. A sound wave undergoes diffraction behind obstacles.

  2. The reflected sound wave at a fixed end interferes with the incident wave.

  3. The longitudinal movement of air molecules produces pressure fluctuations.

  4. The speed of the sound wave changes as its travels through a medium.


Correct Option: C
Explanation:

Longitudinal waves are made up of compressions and rarefactionsCompression happens when molecules are forced, or pressed, together. Rarefaction is just the opposite, it occurs when molecules are given extra space and allowed to expand. So, the longitudinal movement of air molecules produces pressure fluctuations which results in compression and rarefaction.

The science that treats sound generation and transmission by fluid flow is called.

  1. Acoustics

  2. Hydrology

  3. Hydraulics

  4. Aeroacoustics


Correct Option: D

A source emits the sound of frequency $600\ Hz$ inside water. The frequency heard in air will be equal to (velocity of sound in watere$=1500\ m/s$, velocity of sound in air$=300\ m/s$)

  1. $3000\ Hz$

  2. $120\ Hz$

  3. $600\ Hz$

  4. $6000\ Hz$


Correct Option: C
Explanation:

Frequency heard in the air will also be $600\space Hz.$ Whenever, the wave travels from one medium to another medium, its speed and wavelength changes but frequency remains same.

The sound that never changes in pitch, volume, speed or timbre is known as

  1. monologue

  2. monolingual

  3. monophony

  4. monotony


Correct Option: A

The phenomenon of sound propagation in air is 

  1. Isothermal process

  2. Isobaric process

  3. Adiabatic process

  4. None of these


Correct Option: C
Explanation:

the point that there is a local change in temperature due to the compression and rarefaction half$-$ cycles of the waveform and that the these changes occur so quickly that no heat can enter or leave the cycle$,$

So$,$ it callesan adiabatic process$.$
Hence,
option $(C)$ is correct answer.

Mark correct option(s): 

  1. In gas sound wave is always longtudinal wave

  2. In liquid, sound wave is always transverse wave

  3. In solid, sound waves may be transverse wave motion

  4. In solid sound wave may be longitudinal wave motion


Correct Option: D

A sound wave travels from south to north, in which direction do the particles of air move?

  1. west-east

  2. south-north

  3. Up-down

  4. None of these


Correct Option: B
Explanation:

Sound waves are longitudinal waves and the particles of the air move in direction of propagation sound. So if the wave will travel in south-north direction,the particles of the air also travels in south-north direction.

Sound travels in air if

  1. particles of medium travel from one place to another

  2. there is no moisture in the atmosphere

  3. disturbance moves

  4. both particles as well as disturbance travel from one place to another.


Correct Option: C
Explanation:

A wave is a disturbance caused in a medium. In the case of sound, only the disturbances moves causing the surround air molecules to vibrate to and fro. The disturbance is transmitted in the form of compressions and rarefactions.