Tag: sound waves are longitudinal waves

Questions Related to sound waves are longitudinal waves

Fill in the blank.

When sound travels in a medium _______ travels in form of a wave.

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. the source

  2. the particles of the medium

  3. the disturbance

  4. the medium

Show answer
Correct Option: C
Explanation:

When sound travels in a medium the disturbance travels in form of a wave.
Sound is produced when something vibrates. That is, a disturbance is produced. The vibrating body or disturbance causes the medium (water, air, etc.) around it to vibrate. Vibrations in air are called traveling longitudinal waves, which we can hear. Sound waves consist of areas of high and low pressure called compressions and rarefactions, respectively.

The sound waves in a medium are characterised by the

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. linear motion of particle in the medium

  2. rotatory motion of particles in the medium

  3. oscillatory motion of particles in the medium

  4. none of the above

Show answer
Correct Option: C
Explanation:

Sound is a mechanical wave that results from the back and forth vibration of the particles of the medium through which the sound wave is moving. If a sound wave is moving from left to right through air, that is in an oscillatory motion, then particles of air will be displaced both rightward and leftward as the energy of the sound wave passes through it. 

State whether given statement is True or False
A wave is a disturbance that moves through a medium when the particles of the medium set neighboring particles into motion.

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Sound is a mechanical wave that results from the back and forth vibration of the particles of the medium through which the sound wave is moving. If a sound wave is moving from left to right through air, that is in an oscillatory motion, then particles of air will be displaced both rightward and leftward as the energy of the sound wave passes through it. The motion of the particles is parallel (and anti-parallel) to the direction of the energy transport. Here, the sound wave does not move the particles of the medium from one place to another but only the vibration or the disturbance moves. 
Hence, the statement is true.

Fill in the blank. 

In a wave, the particles of the medium do not move forward themselves, but the _________ is carried forward.

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. disturbance

  2. frequency

  3. amplitude

  4. velocity

Show answer
Correct Option: A
Explanation:

In a wave, the particles of the medium do not move forward themselves, but the disturbance is carried forward.
Sound is produced when something vibrates. That is, a disturbance is produced.

Which of the following is NOT correct?

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. more oscillation per second, higher time period

  2. greater amplitude greater loudness

  3. higher pitch, higher frequency of vibration

  4. more the value of decibel, higher is the noise

Show answer
Correct Option: A
Explanation:

Time period $T$ is defined as time taken to complete one oscillation , and frequency $f$ of a wave is defined as the number of oscillations per second ,

                     therefore , $T=1/f$  ,
which gives , more oscillations per second i.e. higher frequency , means smaller time period .

A person can be identified by the quality of sound produced by him. The characteristic of a sound can be determined by:

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. amplitude

  2. frequency

  3. loudness

  4. all of the above

Show answer
Correct Option: D
Explanation:

The characteristics of a sound are :

(i) Loudness or intensity : it distinguishes between a loud or faint sound , and intensity , depends upon amplitude of sound waves .
(ii) Pitch : it distinguishes a sharp sound from a dull sound and pitch depends upon frequency.
(iii) Quality: it distinguishes between sounds generated by two sources .

Which of the following statement is NOT correct?

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. loudness of sound is determined by the amount of energy received by the ear per unit time

  2. pitch doesn't depend upon the amount of energy

  3. loudness changes with change of frequency

  4. pitch changes with change in frequency

Show answer
Correct Option: C
Explanation:

Among all of the above only loudness changes with frequency is the wrong statement as loudness doesn't change with the change of frequency.

Which of the following statements is not true about a sound wave ?

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. Sound travels faster in steel than in air

  2. Sound is a longitudinal wave

  3. The speed of sound in gas is not affected by a change in pressure of the gas

  4. The speed of sound in a gas decreases with increases in the temperature of the gas

Show answer
Correct Option: D
Explanation:
A- Sound travel faster in solid than in gas. Here still is solid and air is gas.
B- Sound is a longitudinal wave as it can travels from one point to another point by to and fro.
C- Speed of sound in gas in independent of pressure and hence the answer.
D- The speed of the sound in a gas increases with the increasing in temperature of the gas. 
Hence D is incorrect ..

Microphone is used to convert

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. Electrical energy into sound energy

  2. Sound energy into electrical energy

  3. Sound energy into mechanical energy

  4. Sound energy into chemical energy

Show answer
Correct Option: B
Explanation:

When we speak on a microphone , our voice (sound energy) is converted in electrical signals (electrical energy) ,which can be transmitted through a wire to a distance . 

Sound waves in the air don't show ______?

physics world of sounds characteristics of sound wave time period, frequency and amplitude of sound sound waves are longitudinal waves

  1. Polarisation

  2. Diffraction

  3. Refraction

  4. Rreflection

Show answer
Correct Option: A
Explanation:

Answer is A.

Sound waves in air travel parallel to the direction that the particles within it oscillate it (definition of a longitudinal wave) - it propagates in 1 dimensional direction. Transverse waves have 2 components (and electric E component, and a magnetic M component). these components propagate at right angles to each other (i.e. it travels in two dimensions). Therefore it is possible to polarize transverse waves. 
Sound waves can be polarized in special conditions.In a solid medium, sound waves can be transverse waves, and in this scenario, the polarization is associated with the direction of the shear stress in the plane perpendicular to the propagation direction.
Hence, Sound waves in air do not show polarization.