Sound Wave MCQ Quiz - Objective Question with Answer for Sound Wave - Download Free PDF

The correct answer is 'Sonic boom'.

Key Points

• Supersonic airplanes generate shock waves, known as Sonic booms.
• It is a type of sound like a thunderclap that basically arises due to the high speed of supersonic aircraft.
• When the speed travels faster than sound and at much higher altitudes due to the shock waves, the "sonic boom" happens.
• When the supersonic aircraft runs at a higher speed then it forms two principal shock fronts, one at its nose and the other at its tail.
• It would sound like 50 ordinary jets taking off at the same time and may cause damage.
• As a supersonic jet moves through the air, it creates a high-energy, cone-shaped wave that trails behind the jet called a "sonic boom".

Additional Information

• Transition waves
  • ​Transition waves sequentially switch bistable elements from one stable configuration to another.
  • They have rich physics and potential applications, including unidirectional propagation, energy harvesting, and mechanical computation. 
• Ultrasound
  • Ultrasound is sound waves with frequencies higher than the upper audible limit of human hearing i.e, humans cannot hear it.
  • Ultrasound devices operate with frequencies from 20 kHz up to several gigahertz.
  • Ultrasound imaging or sonography is often used in medicine.
  • Animals such as bats use ultrasound for locating prey and obstacles.
• Transverse waves
  • ​A transverse wave is a wave whose oscillations are perpendicular to the direction of the wave's advance.
  • This is in contrast to a longitudinal wave which travels in the direction of its oscillations.
  • Water waves are an example of a transverse wave.

The correct answer is Longitudinal.

Key Points

• Sound waves in air are longitudinal waves, where the particles of the medium move in the same direction as the wave propagation.
• In a longitudinal wave, particles oscillate back and forth along the direction of energy transfer, resulting in compressions (high-pressure regions) and rarefactions (low-pressure regions).
• Sound cannot propagate through a vacuum as it requires a material medium like air, water, or solid for the transmission of vibrations.
• Examples of longitudinal waves include sound waves, seismic P-waves, and pressure waves in fluids.
• The speed of sound in air depends on temperature, pressure, and humidity, with an average speed of approximately 343 m/s at 20°C.

Additional Information

• Longitudinal Waves
  • These waves consist of compressions and rarefactions, with energy transfer occurring parallel to particle motion.
  • The wavelength in a longitudinal wave is the distance between two consecutive compressions or rarefactions.
• Transverse Waves
  • In transverse waves, particles of the medium oscillate perpendicular to the direction of wave propagation.
  • Examples include electromagnetic waves (e.g., light) and water surface waves.
• Sound Wave Properties
  • Frequency: Determines the pitch of the sound and is measured in Hertz (Hz).
  • Amplitude: Relates to the loudness or intensity of the sound.
  • Speed: Depends on the medium's density and elasticity.
• Electromagnetic Waves
  • Unlike sound waves, electromagnetic waves (e.g., light, radio waves) do not require a medium for propagation and can travel through a vacuum.

The correct answer is Ultra sonic waves

Key Points

•  Ultrasonic waves are used in the dishwasher or to wash the machines.
• Objects to be cleaned are placed in a cleaning solution and ultrasonic waves are sent into the solution.
• The particles of dust, grease, and dirt get detached and drop out due to the high frequency waves.
• The objects thus get thoroughly cleaned.

Additional Information

Other important uses of Ultrasonic waves are :

• Used to detect cracks and flaws in metal blocks.
• Used for getting images of internal organs of the human body.
• Used to measure the distance, direction and speed of underwater objects.
• Bats search out prey and fly in the dark night by emitting and detecting reflections of ultrasonic waves.

Key Points

• Sound travels fastest in solids because the particles in a solid are closely packed, which facilitates quicker vibration transfer.
• The speed of sound in a solid is much higher compared to liquids and gases due to the solid's higher density and elastic properties.
• In solids, the particles are bound by strong intermolecular forces, allowing sound waves to propagate efficiently.
• For example, sound travels at approximately 5000 m/s in steel, which is significantly higher than its speed in air (~343 m/s).

The correct answer is remains same.

Concept:
Sound

• Sound is a form of energy which produces a sensation of hearing in our ears.
• Sound is produced by vibrating objects. The matter or substance through which sound is transmitted is called a medium. It can be solid, liquid or gas. 

Explanation:

• As the loudness of the mobile ringtone increases, the frequency of the ringtone remains same.
• The loudness is expressed in a unit called decibel (dB). 
• Loudness is the physical response of the ear to the intensity of sound.
• A sound with more energy is referred to as a strong sound.
• Loudness of sound is proportional to the square of the amplitude of the vibration producing the sound. 
• Loudness ∝ (amplitude)²
• The loudness of sound waves does not depend on the frequency of the sound waves. 
• Loudness and Amplitude: Loudness is the perception of how intense or strong a sound seems to our ears. It is directly related to the amplitude of a sound wave.
  • Increasing the amplitude increases the loudness, while decreasing the amplitude decreases the loudness.
• Frequency and Pitch: Frequency is the number of oscillations (cycles) that a sound wave completes in one second, measured in Hertz (Hz).
  • Pitch is the perceptual attribute of the sound that allows us to classify it as higher or lower; it is directly related to the frequency of the sound wave.
  • Higher frequency corresponds to a higher pitch, and lower frequency corresponds to a lower pitch.
• Intensity and Energy: Intensity is the amount of energy a sound wave carries per unit area per unit time, and it is proportional to the square of the amplitude.

Higher intensity results in louder sounds but does not affect the frequency.

Mistake Points

•  Loudness is related to amplitude.
• Pitch is related to frequency.
• Intensity is associated with energy of the sound wave and is proportional to amplitude squared.

Additional Information

• When the amplitude is greater, the loudness of the sound is also higher. 
• When the amplitude is low, the sound produced will be dim.

The correct answer is 850 m.

Key Points

• Echo: If we shout or clap near a suitable reflecting object such as a tall building or a mountain, we will hear the same sound again a little later. This sound which we hear is called an echo.
• Echoes are heard due to the phenomenon of Reflection of sound waves.
• To hear the echo clearly, the reflecting object must be more than 17.2 m from the sound source for the echo to be heard by a person standing at the source.

Additional Information

Given,

Time taken to heard first echo (t₁) = 2 sec

Time taken to heard second echo (t₂) = 3 sec

Velocity of sound (v) = 340 m/s

Let d be the distance between two cliffs, x is the distance between the man and cliff 2, and (d - x) is the distance between the man and cliff 1.

The speed of sound is

\(Speed\;of\;Sound\;\left( v \right) = \frac{{Distance\;\left( d \right)}}{{Time\;\left( t \right)}}\)

The distance between the man and cliff 2 is 

⇒ 2x = v × t₁

\( \Rightarrow x = \frac{{v\; \times\; {t_1}}}{2}\)

\(\Rightarrow x = \frac{{340\; \times \;2}}{2} = 340\;m\)

The distance between the man and cliff 1 is 

⇒ 2(d - x) = v × t₂

\( \Rightarrow \left( {d - x} \right) = \frac{{v\; \times \;{t_2}}}{2}\)

\( \Rightarrow \left( {d - 340} \right) = \frac{{340\; \times \;3}}{2} = 510\)

⇒ d = (510 + 340) m = 850 m

Hence the correct option is 850 m.

The correct answer is remains same.

Concept:
Sound

• Sound is a form of energy which produces a sensation of hearing in our ears.
• Sound is produced by vibrating objects. The matter or substance through which sound is transmitted is called a medium. It can be solid, liquid or gas. 

Explanation:

• As the loudness of the mobile ringtone increases, the frequency of the ringtone remains same.
• The loudness is expressed in a unit called decibel (dB). 
• Loudness is the physical response of the ear to the intensity of sound.
• A sound with more energy is referred to as a strong sound.
• Loudness of sound is proportional to the square of the amplitude of the vibration producing the sound. 
• Loudness ∝ (amplitude)²
• The loudness of sound waves does not depend on the frequency of the sound waves. 
• Loudness and Amplitude: Loudness is the perception of how intense or strong a sound seems to our ears. It is directly related to the amplitude of a sound wave.
  • Increasing the amplitude increases the loudness, while decreasing the amplitude decreases the loudness.
• Frequency and Pitch: Frequency is the number of oscillations (cycles) that a sound wave completes in one second, measured in Hertz (Hz).
  • Pitch is the perceptual attribute of the sound that allows us to classify it as higher or lower; it is directly related to the frequency of the sound wave.
  • Higher frequency corresponds to a higher pitch, and lower frequency corresponds to a lower pitch.
• Intensity and Energy: Intensity is the amount of energy a sound wave carries per unit area per unit time, and it is proportional to the square of the amplitude.

Higher intensity results in louder sounds but does not affect the frequency.

Mistake Points

•  Loudness is related to amplitude.
• Pitch is related to frequency.
• Intensity is associated with energy of the sound wave and is proportional to amplitude squared.

Additional Information

• When the amplitude is greater, the loudness of the sound is also higher. 
• When the amplitude is low, the sound produced will be dim.

The correct answer is Amplitude.

• Loudness means how loud or soft a sound seems to a listener.

Key Points 

• Loudness is related to amplitude and intensity is one of the most salient qualities of a sound which is a measure of the amount of energy in sound waves.
• The unit of intensity is the decibel (dB).

Additional Information

• Speed- The speed of sound is the distance traveled per unit of time by a sound wave when it propagates through an elastic medium.
• Wavelength- The wavelength of a sound is the distance between adjacent identical parts of a wave.
• Frequency- The number of vibrations counted per second is called frequency. The unit of frequency is called hertz (Hz).

The correct answer is 0.04m.

Solution:

Velocity= Frequency* wavelength

Velocity=352m/s

Frequency= 8800Hz

therefore wavelength=velocity/frequency

352/8800=0.04m

hence wavelenght is 0.04 m

The correct answer is Loud sound.

Key Points

• Sound travels as a longitudinal wave.
• A sound wave traveling through air is indeed a longitudinal wave with compressions and rarefactions.
• The study of sound is called acoustics.
• The large amplitude of sound vibrations will produce a loud sound.
  • The intensity of sound is identified by loudness.
  • The loudness of sound is proportional to the square of the amplitude of the vibration producing the sound.
    • If the amplitude of vibration is large, the sound produced is loud.
    • If the amplitude is small, the sound produced is feeble.
  • The loudness of sound depends on the amplitude of vibration of sound-producing objects.
• Sound is a mechanical wave and needs a material medium like air, water, steel.
• The speed of sound depends on the properties of the medium through which it travels.
• Sound cannot travel in a vacuum.
• Sound travels faster in solids.
• The audible range of an average human is 20 Hz — 20 kHz.
• Speed of sound in air = 343 m/s.
• Hertz(Hz) is the unit of the frequency of sound.
• Decibels(dB) is the unit of Intensity of sound.

The correct answer is 600 m.

Here given:

• frequency = 50 Hz,
• wavelength = 4 m.

So, the velocity of wave = Frequency × Wavelength

= 50 × 4

= 200 m/s.
So the distance travelled by the sound wave in 3 s is:

 200 × 3

= 600 m.

The correct answer is Solids.Key Points

• Concept:
  • The speed of the sound depends on the density of the medium through which it is travelling.
  • The particles in the solid medium are closely packed. Hence, the density is high. Information from one molecule to another molecule travels faster in the solid medium.
  • In liquid, the molecules are farther apart than in solids. Hence, the density is low for liquids.
  • In gas, the molecules are very loosely dispersed. The speed of the sound wave will be maximum in steel. 
• Explanation:
  • Sound is a mechanical wave that needs a medium to travel.
  • The speed of sound is maximum in solid, then it is in liquid and it is the slowest in gases.
  • The speed of sound remains almost the same for all frequencies in a given medium under the same physical conditions.
• Notes:
  • The velocity of sound waves in air is 330 m/s. 
  • The velocity of sound waves in steel is 5920 m/s. 
  • The velocity of sound waves in a vacuum is zero. 
  • The velocity of sound waves in water is 1480 m/s. 

The correct answer is WaveLength.

About WaveLength:

• Wavelength is defined as the distance between the Identical points (Crests) in the cycles of a waveform signal which propagated in space or along a wire. In Wireless Systems, this length is usually measured in Centimeters (cm), Millimeters (mm), and Meters (m). It is denoted by the Greek letter Lambda (λ). 
• In a simple manner, if we defined the Wavelength so, the distance between two successive Crest and Trough of a wave. Wavelength is always measured in the direction of the wave. The formula of the Wavelength is represented by (λ =V/F).
• It is traveled from one(1) Crest wave to another wave and from one(1) Trough wave to another of a wave,( Electromagnetic wave, Sound wave, or any other Wave). The Crest is known as the (Highest point) of the wave and the Trough is known as the (Lowest point) of the wave.
• The wavelength of light varies with Colors, every color has a different wavelength. Like Red color has the (longest wavelength) and Violet has the (least wavelength). 
• Wavelength is inversely proportional to Frequency. This means the (Longer) the wavelength, the (Shorter) the Frequency. In another way, (Shorter) the wavelength, (Higher) will be the Frequency.

Image of the Wavelength:

Notes:

• The Amplitude is defined as the maximum extent of an Oscillation or Vibration or oscillation, measured from the position of Equilibrium. It is denoted as (A). Its SI unit is the meter (m).
• Frequency is defined as the rate at which something occurs over a particular (period of time). It is denoted as (F) and the unit is Hertz.
• Wave Number is defined as the number of Waves in a unit distance travels by the sound wave. Its unit is measured in meters (1/m).

The correct answer is only longitudinal.

Concept:

• Sound wave: The longitudinal wave in an elastic medium that produces an audible sensation is called a sound wave.
  • As sound waves are longitudinal waves, the air particles vibrate to and fro in the direction of propagation of sound.
  • It is a wave of compression and rarefaction.
  • Compressions and rarefactions are part of a sound wave.

• Compression: A region in a longitudinal wave where the particles are closest together is called compression. Compression has high density and high pressure

  Rarefaction: A region in a longitudinal wave where the particles are furthest apart is called rarefaction. The rarefaction has a low density and low pressure

Key Points

• Longitudinal waves- The particles displaced in this type of waves are parallel to the direction the wave travels.
  • Sound waves are longitudinal waves. 
  • The sound waves are longitudinal waves because particles of the medium through which the sound travels vibrate parallel to the direction that the sound wave moves.

Additional Information

• Transverse wave - The particles displaced in this type of waves are perpendicular to the direction the wave travels.
  • In light waves, the oscillations of the electric and magnetic fields are transverse.

The correct answer is Ultra sonic waves

Key Points

•  Ultrasonic waves are used in the dishwasher or to wash the machines.
• Objects to be cleaned are placed in a cleaning solution and ultrasonic waves are sent into the solution.
• The particles of dust, grease, and dirt get detached and drop out due to the high frequency waves.
• The objects thus get thoroughly cleaned.

Additional Information

Other important uses of Ultrasonic waves are :

• Used to detect cracks and flaws in metal blocks.
• Used for getting images of internal organs of the human body.
• Used to measure the distance, direction and speed of underwater objects.
• Bats search out prey and fly in the dark night by emitting and detecting reflections of ultrasonic waves.