1. This is a list of the many media.
i. wood
ii. Water
iii. air
iv. Vacuum
Which of these enables sound to travel?
(a) i & ii only
(b) i, ii & iii only
(c) iii & iv only
(d) ii, iii & iv only
1. This is a list of the many media.
i. wood
ii. Water
iii. air
iv. Vacuum
Which of these enables sound to travel?
(a) i & ii only
(b) i, ii & iii only
(c) iii & iv only
(d) ii, iii & iv only
Explanation:
Option (b): just I ii, and iii
Vibrations create a sort of energy known as sound.
The molecules of the air around an object move when it vibrates.
As these molecules come into contact with neighboring molecules, it causes them to vibrate as well.
Sound is a sequence of pressure waves that move through compressible media like air or water throughout its propagation. (While there are other methods for sound to travel, it can also travel through solids.)
The medium can cause waves to be reflected, refracted, or attenuated as they go through it.
2. A sound's volume is determined by:
(a) the size of it.
(b)its frequency
(c) the duration of it.
(d) How fast it is.
2. A sound's volume is determined by:
(a) the size of it.
(b)its frequency
(c) the duration of it.
(d) How fast it is.
Explanation:
The amplitude is the correct response (a).
Explanation: The loudness of anything is directly correlated with the amplitude of sound waves. The sound will be louder if the amplitude is greater, and weaker if the amplitude is smaller. The intensity or loudness of the sound depends on the degree of vibration, or amplitude of vibration, of the sounding body. A sound's intensity rises as the vibration's amplitude grows and decreases as it gets further away from its source. Loudness is measured using decibels.
Amplitude squared has an inverse relationship with loudness.
3. Which of the subsequent claims is true?
i. Vibrations generate sound.
ii. For sound to travel, a medium is needed.
iii. A medium is necessary for the propagation of both light and sound.
iv. Sound travels more slowly than light
(a) i & ii only
(b) i, ii & iii only
(c) ii, iii & iv only
(d) i, ii & iv only
3. Which of the subsequent claims is true?
i. Vibrations generate sound.
ii. For sound to travel, a medium is needed.
iii. A medium is necessary for the propagation of both light and sound.
iv. Sound travels more slowly than light
(a) i & ii only
(b) i, ii & iii only
(c) ii, iii & iv only
(d) i, ii & iv only
Explanation:
The correct response is (d) I ii, and iv alone
Explanation: Statement iii) is incorrect since light and sound are two distinct phenomena. The correct response is (d) I ii, and iv alone. Only sound needs an intermediary to travel; light may go through a vacuum. Sound requires a material medium like a solid, liquid, or gas to move because the molecules of solids, liquids, and gases transfer sound waves from one place to another.
4. At 50 Hz, something is vibrating. What timeframe does it cover?
(a) 0.02 s
(b) 2 s
(c) 0.2 s
(d) 20.0 s
4. At 50 Hz, something is vibrating. What timeframe does it cover?
(a) 0.02 s
(b) 2 s
(c) 0.2 s
(d) 20.0 s
Explanation:
It is (a) 0.02 s is the correct option.
Explanation:If something is moving at 50 hertz
50 = 1/T
T = 1/50
T = 0.02s
It will last for 0.02 seconds
5. We need to in order to lessen the volume of a sound
(A) reduce the sound's vibration frequency.
(b) raise the sound's vibrational frequency.
(c) lessen the sound's vibrational amplitude.
(d) enhance the sound's vibrational amplitude.
5. We need to in order to lessen the volume of a sound
(A) reduce the sound's vibration frequency.
(b) raise the sound's vibrational frequency.
(c) lessen the sound's vibrational amplitude.
(d) enhance the sound's vibrational amplitude.
Explanation:
The correct response is (c) reduce the sound's vibrational amplitude.
The loudness of a sound is precisely proportional to its volume, as explained. As a result, when amplitude falls, so does sound volume. The correct response is to reduce the sound's vibrational amplitude. As the amplitude determines the loudness, increasing the amplitude will increase the loudness of the sound, and decreasing the amplitude would lower the loudness of the sound. Option C is the right response, thus.
6. Sound volume is expressed in
(a) decibels (dB)
(b) hertz (Hz)
(c) Meter (m)
(d) and Second (m/s)
6. Sound volume is expressed in
(a) decibels (dB)
(b) hertz (Hz)
(c) Meter (m)
(d) and Second (m/s)
Explanation:
the correct option is A Decibel (dB) (dB)
Explaination: A sound's intensity is calculated by dividing its wattage by the square metres of space it travels through. Each given sound's intensity is related to its intensity at the hearing threshold by its loudness. Decibels are used to measure it (dB).
7. The factors that affect the loudness of sound include
(a) Vibrational amplitude
(b) the vibration's ratio of amplitude to frequency
(c) the vibrational frequency
(d) the result of the vibration's amplitude and frequency
7. The factors that affect the loudness of sound include
(a) Vibrational amplitude
(b) the vibration's ratio of amplitude to frequency
(c) the vibrational frequency
(d) the result of the vibration's amplitude and frequency
Explanation:
The answer is (a) vibration amplitude.
Explanation: The amplitude of sound waves directly relates to how loud something is. When the product of the vibration's amplitude and frequency is high, the sound will be louder, and when it is low, the sound will be weak. Although frequency of vibration is unrelated to loudness or intensity of sound, it does rely on the amplitude of vibration. As a result, the relationship between vibration's amplitude and frequency does not affect how loud a sound is.
8. the same as 1 hertz is
(a)One vibration per minute
(b)10 vibrations per minute
(c) 60 rpm of vibration
(d) 600 rpm of vibration
8. the same as 1 hertz is
(a)One vibration per minute
(b)10 vibrations per minute
(c) 60 rpm of vibration
(d) 600 rpm of vibration
Explanation:
The correct response is (c) 60 rpm.
Explanation: 1Hz Equals 1 vibration per second.
Given that one hertz equals 60 vibrations per minute in a minute,
The measure of frequency is the hertz. The frequency of an ac sine wave is the number of cycles per second. The pace at which the current changes direction each second is known as frequency. As there are one cycle every second in a hertz, there are 60 vibrations each minute in a hertz.
9. The sound's pitch is governed by its
(a) Regularity
(b)amplitude
(c) Fastness
(d) Volume
9. The sound's pitch is governed by its
(a) Regularity
(b)amplitude
(c) Fastness
(d) Volume
Explanation:
The right response is (A). The frequency of a sound affects its pitch.
Explanation: Recall that the pitch rises with rising frequency and falls with falling frequency. Our ears are not designed to handle sounds with unstable frequencies. It may possibly result in hearing loss or a severe headache.
10. There is a vibrational frequency to ultrasound.
(a) 20,000 to 20,000 Hz
(b) lower than 20 Hz
(c) more than 20,000 Hz
(d) 500 and 10,000 hertz
10. There is a vibrational frequency to ultrasound.
(a) 20,000 to 20,000 Hz
(b) lower than 20 Hz
(c) more than 20,000 Hz
(d) 500 and 10,000 hertz
Explanation:
Option C, "Ultrasound has frequency of vibration exceeding 20,000 Hz," is the right response.
Explanation: The sole physical distinction between ultrasound and "normal" (audible) sound is that humans cannot hear ultrasound, which is why higher frequency sound waves above the top audible range of human hearing are known as ultrasound.
11. One might think of lightning as the instant it happens. Paheli notices lightning in her neighbourhood. Five seconds after seeing the lightning, she hears the sound. How far away is she from the location of the lightning? (Sound speed is 330 m/s).
11. One might think of lightning as the instant it happens. Paheli notices lightning in her neighbourhood. Five seconds after seeing the lightning, she hears the sound. How far away is she from the location of the lightning? (Sound speed is 330 m/s).
Explanation:
Distance = 330ms times 5s = 1650m
Explanation: Distance equals Speed minus Time. The distance travelled may be computed using the following formula where the time taken is 5 seconds and the speed of sound in air is 330 metres per second. D=330m/s×5s=1650m Paheli is thus 1.65 kilometres away from the lightning strike.
12. Does anything on our bodies vibrate when we talk? Provide the component's name.
12. Does anything on our bodies vibrate when we talk? Provide the component's name.
Explanation:
The larynx, or voice box, is used by humans to produce sound.
It is situated at the top of the windpipe (trachea).
The larynx has two ligaments known as vocal cords.
These vocal cords vibrate, producing sound.
While we speak, the muscles that support the vocal cords flex and shut two vocal cords so closely that there is barely any space between them.
The lungs carry air across the two vocal cords, causing the vocal cords to vibrate and produce sound.
Consequently, the vocal cords' vibrations produce the sound we hear when we speak.
13. At night, Boojho observed a cracker explode far from his home. Later, after witnessing the cracker break, he heard the cracker's sound. Describe the cause of the delay in sound perception.
13. At night, Boojho observed a cracker explode far from his home. Later, after witnessing the cracker break, he heard the cracker's sound. Describe the cause of the delay in sound perception.
Explanation:
Boojho heard the sound of the cracker after witnessing it burst because the speed of light is quicker than the speed of sound.
Later, after witnessing the cracker break, he heard the cracker's sound. Describe the cause of the delay in sound perception. As light travels at a faster pace than sound, Boojho heard the cracker's sound after first witnessing its explosion.
14. Is there any portion of our body that vibrates when we hear a sound? Specify the component.
14. Is there any portion of our body that vibrates when we hear a sound? Specify the component.
Explanation:
Certain components in our ears translate sound waves into electrical signals that the brain can interpret. Every time we hear a sound, our eardrum, which is a portion of the middle ear, vibrates, allowing the sound to go to the inner ear.
15. What are two musical instruments that use vibrating strings to create sound?
15. What are two musical instruments that use vibrating strings to create sound?
Explanation:
Stringed instruments, often known as strung instruments, are musical instruments whose strings vibrate to create sound. When most string instruments communicate their vibrations to the body, the air inside it vibrates as well.
The violin, guitar, sitar, electric bass, viola, cello, harp, double bass, banjo, and mandolin are examples of common stringed instruments.
16. In 20 seconds, a basic pendulum oscillates ten times. How long does it oscillate for, and how often?
16. In 20 seconds, a basic pendulum oscillates ten times. How long does it oscillate for, and how often?
Explanation:
Period: 2 seconds
0.5 oscillations per second.
Explanation: In 20 seconds, a pendulum oscillates ten times.
So, 1 oscillation in 20/10 seconds is 2 seconds.
time=2 seconds
Frequency is equal to 1/t = 1/2 = 0.5 Hz.
A basic pendulum will oscillate 10 times in 20 seconds; each oscillation will last 2 seconds. As a result, because the duration is determined to be 2 seconds, the oscillation's frequency is given by 1/T = 1/ 2 = 0.5 Hertz.
17. We now know that sound production requires vibration. Why can't we hear the sound that every vibrating body produces?
17. We now know that sound production requires vibration. Why can't we hear the sound that every vibrating body produces?
Explanation:
Everyone has a unique frequency range. Yet, because our hearing range is limited to 20 Hz to 2000 Hz, we are unable to hear the sound of a few vibrating bodies. While it is true that vibrations are essential for the creation of sound, the human hearing range only extends from 20 Hz to 20 kHz, making it impossible for us to perceive any vibrating object. The Best Response! As sound is produced, three things vibrate: the source item, air molecules, and the eardrum.
18. Imagine that a frying pan gets struck by a stick in a hoover. The cooking pan may vibrate. Will the sound be audible to us? Explain.
18. Imagine that a frying pan gets struck by a stick in a hoover. The cooking pan may vibrate. Will the sound be audible to us? Explain.
Explanation:
The cooking pan starts to shake. Sound cannot travel in a hoover, thus we won't be able to hear the sound of vibration. As there are no molecules in a hoover that can vibrate and convey the sound wave, sound cannot travel through it. Hence, the frying pan will vibrate when hit with a stick. Nevertheless, since there are no molecules in a hoover, the sound wave cannot travel. There will therefore be vibration but no sound.
19. Two astronauts are seated next to one another in orbit. Are they able to converse without a special device? Cite your reasons.
19. Two astronauts are seated next to one another in orbit. Are they able to converse without a special device? Cite your reasons.
Explanation:
Sound waves can only travel through the vacuum in outer space.
Without using any special technology, the two astronauts are floating near to one another in space but are now unable to converse with one another due to the distance between them. No air exists between them, hence there are no air molecules or other microscopic components to carry sound through. They are unable to communicate as a result.
20. In your area, name three sources of noise pollution.
20. In your area, name three sources of noise pollution.
Explanation:
The following are some of the main causes of noise pollution:
Vehicle noise, such as that from automobiles, buses, scooters, etc.
Kitchen appliance noises, such as those from a juicer, blender, mixer, etc.
sound of crackers exploding
the sound of television, transistors, loudspeakers, industrial alarms, honking cars, and crackers bursting. are other instances of noise.
21. We have an instrument with strings. A force of higher size is used to pull the centre of the string first, followed by a force of lesser magnitude. If so, would the sound the instrument makes be louder?
21. We have an instrument with strings. A force of higher size is used to pull the centre of the string first, followed by a force of lesser magnitude. If so, would the sound the instrument makes be louder?
Explanation:
The vibration's amplitude controls how loud the sound is. The amplitude of a string will increase with increased force applied to it. The sound is louder as a result.
As the amplitude is bigger in this situation and loudness relies on the amplitude, it will produce a louder sound when the string is stretched with more effort. The loudness and amplitude will increase as volume increases.
22. How is sound created, transferred, and perceived by us?
22. How is sound created, transferred, and perceived by us?
Explanation:
When the body begins vibrating under any kind of stress, sound is created. This vibration generates waves, which pass via a medium on their way to our ears, where they are heard.
By our ears, we can hear the sound. The outer portion of the ear has a funnel-like appearance. As sound enters it, it travels down a canal to a thin, stretched membrane at the end of the canal. It's known as the eardrum.The eardrum looks like a rubbery chunk that has been stretched out.The eardrum vibrates as a result of the sound waves. From there, the signal continues on to the brain. In that manner, we hear. A vibrating item has the potential to create and transfer sound, a type of energy. Across the physical cosmos, it oscillates back and forth in a manner like to waves. The eardrum vibrates as a result of this wave striking it. Once the sound has arrived, the signal is processed by the brain so that humans can hear it.
23. As seen in Fig. 13.1, an alarm bell is maintained within a container. The alarm's sound may be clearly heard by someone standing close by. How would the volume of the alert change for the same individual if all of the air in the vessel is removed?
23. As seen in Fig. 13.1, an alarm bell is maintained within a container. The alarm's sound may be clearly heard by someone standing close by. How would the volume of the alert change for the same individual if all of the air in the vessel is removed?
Explanation:
In order to be conveyed, air requires a medium. If the bottle's inside air is gradually removed. Due to the hoover, sound won't have a medium to travel on. Because to hoover, the sound's volume steadily decreases as the bottle's air content increases. As long as there was air inside the container, the required medium for sound transmission was also there. Yet, there is a hoover in the vessel when the air is taken out. As sound cannot travel through a hoover, no one standing close to the vessel will be able to hear the ringing of the bell.
24. Next to Boojho's home lies the town hall structure. The bell of the town hall is rung every hour by a clock that is located on its roof. Boojho has noted that the clock's tone is audibly more distinct at night. Explain.
24. Next to Boojho's home lies the town hall structure. The bell of the town hall is rung every hour by a clock that is located on its roof. Boojho has noted that the clock's tone is audibly more distinct at night. Explain.
Explanation:
Speed, pitch, and loudness are all started with vibration when sound is produced. There are many vibrations present in the daytime all around us. As a result, the vibrations' amplitude decreases. There won't be any such annoyances at night, making the music clearer. There are a lot of vibrations in the air during the day. These vibrations lessen the clock's bell's volume, pitch, and speed. Boojho may therefore hear the watch's bell considerably more clearly at night than during the day.
25. Provide three recommendations for reducing noise pollution in your area.
25. Provide three recommendations for reducing noise pollution in your area.
Explanation:
The following actions are suggested to reduce noise pollution in our area:
Industries that generate noise have to be located away from residential areas.
The volume of the television and music systems should be kept low.
Silencing devices must be fitted in the engines of aeroplanes, transport vehicles, industrial machinery, and residential appliances.
It is necessary to grow trees near the buildings and along the highways.
Horn use needs to be kept to a minimum.
Industrial equipment and transportation vehicles both require the installation of silencers.
26. Draw a picture of the larynx and describe it in your own words.
26. Draw a picture of the larynx and describe it in your own words.
Explanation:
Larynx is a component of the throat, therefore yes. When we ingest anything, it moves. The larynx has two voice cords. There is a tiny space between them where the air may travel. As we talk, the lungs push air into the room, which causes the vocal cord to vibrate and produce sound. The larynx is also referred to as a sound box because of this.
