Sound

Question 1
What causes the production of sound in various musical instruments?
a) Electrical energy
b) Mechanical vibrations
c) Chemical reactions
d) Light energy

Answer: b) Mechanical vibrations
Explanation: Sound in musical instruments is produced by mechanical vibrations. For instance, when a guitar string is plucked, it vibrates and creates sound.

Question 2
In human beings, where is the sound produced?
a) In the lungs
b) In the brain
c) In the voice box or larynx
d) In the mouth

Answer: c) In the voice box or larynx
Explanation: In humans, sound is produced in the voice box or larynx. The air forced through the vocal cords causes them to vibrate, producing sound.

Question 3
Which of the following is necessary for sound to travel?
a) A vacuum
b) A medium like air, water, or solids
c) High temperature
d) Light

Answer: b) A medium like air, water, or solids
Explanation: Sound needs a medium like air, water, or solids to travel. It cannot travel through a vacuum.

Question 4
What is the audible range of sound for human ears?
a) 2 Hz to 20 Hz
b) 20 Hz to 2,000 Hz
c) 20 Hz to 20,000 Hz
d) 20,000 Hz to 2,000,000 Hz

Answer: c) 20 Hz to 20,000 Hz
Explanation: The human ear can hear sounds in the range of 20 Hz to 20,000 Hz. Sounds outside this range are inaudible to humans.

Question 5
What determines the pitch of a sound?
a) Amplitude of the sound wave
b) Frequency of the sound wave
c) Loudness of the sound
d) Medium through which sound travels

Answer: b) Frequency of the sound wave
Explanation: The pitch of a sound is determined by its frequency. High-frequency sounds have a high pitch, and low-frequency sounds have a low pitch.

Question 6
Which of the following is true about noise pollution?
a) It is always harmful and unpleasant.
b) It is a type of musical sound.
c) It can never be controlled.
d) It only occurs in urban areas.

Answer: a) It is always harmful and unpleasant.
Explanation: Noise pollution refers to unwanted, unpleasant sounds that can cause harm and discomfort.

Question 7
What is the role of the eardrum in hearing?
a) It generates sound waves.
b) It vibrates in response to sound waves.
c) It converts sound waves into light.
d) It is not involved in the hearing process.

Answer: b) It vibrates in response to sound waves.
Explanation: The eardrum vibrates when sound waves hit it. These vibrations are then transmitted to the inner ear, where they are converted into electrical signals for the brain to interpret.

Question 8
What happens when the amplitude of a sound wave increases?
a) The sound becomes quieter.
b) The pitch of the sound increases.
c) The sound becomes louder.
d) The frequency of the sound decreases.

Answer: c) The sound becomes louder.
Explanation: The amplitude of a sound wave is directly related to its loudness. Higher amplitude means a louder sound.

Question 9
When a school bell is struck, what type of sound waves are produced?
a) Transverse waves
b) Longitudinal waves
c) Electromagnetic waves
d) Static waves

Answer: b) Longitudinal waves
Explanation: Sound waves are longitudinal waves where the displacement of the medium is parallel to the direction of the wave’s travel.

Question 10
What is the term used to describe the number of complete back-and-forth vibrations of a particle in one second?
a) Amplitude
b) Wavelength
c) Frequency
d) Velocity

Answer: c) Frequency
Explanation: Frequency refers to the number of complete oscillations per second. It is measured in hertz (Hz).

Question 11
Why do men generally have deeper voices than women?
a) Men’s vocal cords vibrate more slowly.
b) Men’s vocal cords vibrate more quickly.
c) Men’s vocal cords are shorter and thinner.
d) Men’s vocal cords are longer and thicker.

Answer: d) Men’s vocal cords are longer and thicker.
Explanation: Men typically have longer and thicker vocal cords, which vibrate more slowly, producing a deeper voice.

Question 12
What does the decibel (dB) measure?
a) Frequency of a sound
b) Pitch of a sound
c) Loudness of a sound
d) Speed of sound

Answer: c) Loudness of a sound
Explanation: Decibel is a unit that measures the intensity or loudness of a sound.

Question 13
In which of these media would sound travel the fastest?
a) Air
b) Water
c) Steel
d) Vacuum

Answer: c) Steel
Explanation: Sound travels fastest in solids, and among the options given, steel (a solid) would conduct sound the fastest.

Question 14
What kind of sound is produced by a vibrating object with a low frequency?
a) Shrill
b) High-pitched
c) Low-pitched
d) Ultrasonic

Answer: c) Low-pitched
Explanation: Low-frequency vibrations produce low-pitched sounds.

Question 15
Which factor does not affect the speed of sound?
a) Temperature of the medium
b) Pressure of the medium
c) Color of the medium
d) Density of the medium

Answer: c) Color of the medium
Explanation: The color of the medium does not affect the speed of sound. Factors like temperature, pressure, and density do have an impact.

Question 16
What is the primary function of the ear drum in the human auditory system?
a) To amplify sound
b) To convert sound into electrical signals
c) To vibrate in response to sound waves
d) To protect the inner ear

Answer: c) To vibrate in response to sound waves
Explanation: The eardrum vibrates when sound waves strike it, and these vibrations are then transmitted to the inner ear.

Question 17
Which part of the human ear amplifies the sound?
a) Ear drum
b) Cochlea
c) Ear canal
d) Auditory ossicles

Answer: d) Auditory ossicles
Explanation: The auditory ossicles, comprising the malleus, incus, and stapes, amplify the sound vibrations received from the eardrum.

Question 18
What is the role of the cochlea in the human ear?
a) It amplifies sound waves.
b) It transmits sound waves to the eardrum.
c) It converts sound waves into electrical signals.
d) It protects the inner ear.

Answer: c) It converts sound waves into electrical signals.
Explanation: The cochlea, filled with fluid and lined with thousands of tiny hair cells, converts the sound vibrations into electrical signals sent to the brain.

Question 19
Which of the following is an example of a stringed musical instrument?
a) Drum
b) Flute
c) Sitar
d) Trumpet

Answer: c) Sitar
Explanation: The sitar is a stringed musical instrument where sound is produced by the vibration of strings.

Question 20
What happens to the pitch of a sound when its frequency decreases?
a) The pitch increases.
b) The pitch decreases.
c) The pitch remains the same.
d) The pitch becomes ultrasonic.

Answer: b) The pitch decreases.
Explanation: Lower frequency results in a lower pitch. Thus, as the frequency decreases, the pitch of the sound also decreases.

Question 21
Which of the following is not a characteristic of sound?
a) Pitch
b) Loudness
c) Color
d) Frequency

Answer: c) Color
Explanation: Color is not a characteristic of sound. Pitch, loudness, and frequency are key characteristics of sound.

Question 22
How does sound travel through air?
a) By transverse waves
b) By longitudinal waves
c) By electromagnetic waves
d) In a straight line without a medium

Answer: b) By longitudinal waves
Explanation: Sound travels through air as longitudinal waves, where particles of the medium vibrate back and forth in the direction of the wave’s travel.

Question 23
In the context of sound, what does the term ‘ultrasound’ refer to?
a) Sounds with frequencies below the human audible range
b) Sounds with frequencies within the human audible range
c) Sounds with frequencies above the human audible range
d) The highest frequency sound a human can hear

Answer: c) Sounds with frequencies above the human audible range
Explanation: Ultrasound refers to sounds with frequencies above the human audible range, typically above 20,000 Hz.

Question 24
Which of the following instruments is most likely to produce high-pitched sound?
a) Drum
b) Cello
c) Violin
d) Tubular bells

Answer: c) Violin
Explanation: The violin, due to its smaller size and tighter strings, typically produces high-pitched sounds.

Question 25
What is the primary cause of the difference in voices among people?
a) The shape of the mouth
b) The size of the lungs
c) The length and thickness of vocal cords
d) The amount of air inhaled

Answer: c) The length and thickness of vocal cords
Explanation: The variation in voice among individuals is primarily due to differences in the length and thickness of the vocal cords.

Question 26
Which of the following statements is true about sound?
a) It can travel faster in solids than in gases.
b) It travels faster in a vacuum than in air.
c) It does not require a medium for propagation.
d) It always travels at the same speed in all media.

Answer: a) It can travel faster in solids than in gases.
Explanation: Sound travels faster in solids than in gases because particles in solids are closer together, facilitating quicker vibration transfer.

Question 27
What is the effect of temperature on the speed of sound?
a) Sound travels faster in colder temperatures.
b) Sound travels slower in colder temperatures.
c) Temperature has no effect on the speed of sound.
d) Sound travels at the same speed regardless of temperature.

Answer: b) Sound travels slower in colder temperatures.
Explanation: Sound travels faster in warmer temperatures because the particles in the medium move more rapidly, allowing sound waves to travel more quickly.

Question 28
Which of these is an example of an instrument that uses air vibration to produce sound?
a) Drum
b) Guitar
c) Flute
d) Violin

Answer: c) Flute
Explanation: The flute is a wind instrument that produces sound through the vibration of air within its tube.

Question 29
What determines the loudness of a sound?
a) The color of the sound wave
b) The length of the sound wave
c) The amplitude of the sound wave
d) The speed of the sound wave

Answer: c) The amplitude of the sound wave
Explanation: The loudness of a sound is directly proportional to the amplitude of the sound wave. Higher amplitude results in a louder sound.

Question 30
Which of these frequencies is likely to be inaudible to humans?
a) 15 Hz
b) 250 Hz
c) 1,000 Hz
d) 15,000 Hz

Answer: a) 15 Hz
Explanation: Humans generally cannot hear sounds with frequencies lower than 20 Hz, making 15 Hz inaudible to humans.

Question 31
In which of these environments would you expect sound to travel the slowest?
a) Through steel
b) Through water
c) Through air
d) Through vacuum

Answer: d) Through vacuum
Explanation: Sound cannot travel through a vacuum as there are no particles to transmit the sound waves.

Question 32
Which of the following best describes the effect of noise pollution?
a) It is always pleasant and harmless.
b) It can cause health problems like stress and hearing loss.
c) It increases concentration and productivity.
d) It has no effect on humans or animals.

Answer: b) It can cause health problems like stress and hearing loss.
Explanation: Noise pollution can lead to various health issues including stress, hearing loss, sleep disturbances, and more.

Question 33
What is the phenomenon called when sound waves bounce back after hitting a surface?
a) Refraction
b) Diffraction
c) Absorption
d) Reflection

Answer: d) Reflection
Explanation: Reflection of sound occurs when sound waves bounce back upon encountering an obstacle. This phenomenon is similar to the reflection of light.

Question 34
Which of the following is used in sonography?
a) Infrasound
b) Audible sound
c) Ultrasound
d) Radio waves

Answer: c) Ultrasound
Explanation: Sonography uses ultrasound, which are sound waves with frequencies higher than the audible range for humans (above 20,000 Hz).

Question 35
How is the human voice produced?
a) By the vibration of bones
b) By the movement of lips
c) By the vibration of vocal cords
d) By the flow of blood

Answer: c) By the vibration of vocal cords
Explanation: The human voice is produced by the vibration of the vocal cords located in the larynx or voice box.

Question 36
Why is sound heard more clearly on a rainy day than on a dry day?
a) Rain absorbs noise pollution
b) Raindrops amplify sound waves
c) Humidity increases sound wave speed
d) Rain changes the direction of sound

Answer: c) Humidity increases sound wave speed
Explanation: On a rainy day, increased humidity in the air lowers the density of the air, allowing sound waves to travel faster and more clearly.

Question 37
What is the unit for measuring the frequency of sound?
a) Decibel (dB)
b) Hertz (Hz)
c) Newton (N)
d) Pascal (Pa)

Answer: b) Hertz (Hz)
Explanation: The frequency of sound is measured in Hertz (Hz), which represents the number of cycles per second.

Question 38
What happens to the pitch of a musical note when the length of a vibrating string is shortened?
a) The pitch decreases
b) The pitch remains unchanged
c) The pitch increases
d) The pitch becomes inaudible

Answer: c) The pitch increases
Explanation: Shortening the length of a vibrating string increases its frequency, resulting in a higher pitch.

Question 39
Which of the following is a characteristic feature of sound waves?
a) They are electromagnetic waves
b) They require a medium to travel
c) They can travel through a vacuum
d) They travel fastest in gases

Answer: b) They require a medium to travel
Explanation: Sound waves are mechanical waves that require a medium (like air, water, or solids) to travel. They cannot propagate through a vacuum.

Question 40
What is the effect of increasing the tension in a stringed musical instrument?
a) The pitch of the sound decreases
b) The loudness of the sound decreases
c) The pitch of the sound increases
d) The quality of the sound becomes poorer

Answer: c) The pitch of the sound increases
Explanation: Increasing the tension in the strings of a musical instrument raises their frequency of vibration, resulting in a higher pitch.

Question 41
Which characteristic of a sound wave determines its loudness?
a) Frequency
b) Wavelength
c) Amplitude
d) Speed

Answer: c) Amplitude
Explanation: The loudness of a sound is determined by its amplitude. Larger amplitude results in a louder sound.

Question 42
Which of the following animals can hear ultrasonic sounds that humans cannot?
a) Cats
b) Dogs
c) Elephants
d) Cows

Answer: b) Dogs
Explanation: Dogs can hear ultrasonic sounds, which are frequencies higher than the human audible range (above 20,000 Hz).

Question 43
What is the main difference between musical sounds and noise?
a) Musical sounds are always loud, while noise is soft.
b) Musical sounds have a specific pitch; noise does not.
c) Noise is produced by musical instruments, while musical sounds are not.
d) Musical sounds are unpleasant, while noise is pleasant.

Answer: b) Musical sounds have a specific pitch; noise does not.
Explanation: Musical sounds are organized and have a specific pitch and rhythm, whereas noise is disorganized and lacks a specific pitch.

Question 44
In which of the following mediums will sound travel the fastest?
a) Air
b) Water
c) Steel
d) Oil

Answer: c) Steel
Explanation: Sound travels fastest in solids, and among the given options, steel (a solid) has the highest sound transmission speed.

Question 45
What happens to the speed of sound when it passes from air to water?
a) It increases
b) It decreases
c) It remains the same
d) It becomes zero

Answer: a) It increases
Explanation: Sound travels faster in water than in air because water is denser than air, allowing sound waves to transmit more efficiently.

Question 46
Which of the following does NOT affect the speed of sound in a medium?
a) The medium’s temperature
b) The medium’s density
c) The loudness of the sound
d) The pressure of the medium

Answer: c) The loudness of the sound
Explanation: The speed of sound in a medium is affected by factors like temperature, density, and pressure, but not by the loudness of the sound.

Question 47
What type of sound waves are produced by the human vocal cords?
a) Transverse waves
b) Longitudinal waves
c) Electromagnetic waves
d) Surface waves

Answer: b) Longitudinal waves
Explanation: The human vocal cords produce longitudinal sound waves, where the particles of the medium vibrate parallel to the direction of wave propagation.

Question 48
Why is it difficult to hear sound on the moon?
a) Because the moon is too far from Earth
b) Because the moon’s atmosphere absorbs sound
c) Because there is no air on the moon to transmit sound
d) Because sound waves are scattered by the moon’s surface

Answer: c) Because there is no air on the moon to transmit sound
Explanation: The moon has no atmosphere (air), and since sound waves require a medium to travel, sound cannot propagate on the moon.