Education Journalist | Study Abroad Lead
Acoustics is the science of sound production, transmission, and propagation. The word ‘Acoustic’ is derived from the Greek words ‘Akoustikos’ (meaning ‘of or for the hearing/ready to hear’) and ‘Akoustos’, (meaning ‘heard or audible’). Acoustics is being used in a variety of sectors like healthcare, military, the construction sector, and so on. A sound-absorbing substance is beneficial for decreasing noise. Let’s understand what is acoustics, acoustics energy, types and discuss some important questions
| Table of Contents |
Key Terms: Acoustics, Ultrasound, Infrasound, Acoustics Energy, Reverberation, Application of Acoustics, Condition of Acoustics, Transduction, Vibration, Dynamics, Sound Waves
Check also: Inaudible Audible Sound
What is Acoustics?
[Click Here for Sample Questions]
Acoustics is the field of physics that is focused on the study of sound. Acoustics can be defined as "the science that examines sound and its origin, transmission, and effects." An acoustician refers to a professional or scientist who studies acoustics, whereas Acoustical Engineering refers to the one who works in the area of acoustics technologies. Originally, acoustics was usually utilized in sectors that rely on sounds, such as auditoriums and theatres, but now, acoustics is used in a wide range of fields. There are several areas of study in acoustics. You could investigate the generation, control, transfer, absorption, or impacts of sound on people, animals, or even objects if you learn acoustics.
Acoustics
The video below explains this:
Acoustics Detailed Video Explanation:
Read more: Sound Produced by Humans
What is Acoustics Energy?
[Click Here for Sample Questions]
The interruption of energy that travels through a substance in the form of waves is referred to as acoustic energy. Sound waves are an example of acoustic energy. When sound passes through any medium, it creates waves of vibrations.
To put it another way, acoustic energy is defined as the energy-related to mechanical vibrations from its constituents. The stages of the acoustic event are as follows:
- Cause or Generating Mechanism
- Acoustic wave propagation
- Reception Effect
The transduction process is the conversion of any form of energy into acoustic energy, resulting in a sound wave. The energy of sound waves is transmitted throughout the transmitting medium. The primary equation that determines sound wave propagation is the acoustic wave equation. Wave propagation is the most important aspect of any acoustic activity. In liquids, sound travels as a pressure wave, while in solids, it travels as longitudinal waves or transverse waves.
Acoustic Energy Loudspeakers
Also Read: Difference between Transverse and Longitudinal Waves
Types of Acoustics
[Click Here for Sample Questions]
-
Environmental Noise
Environmental acoustics analyzes the vibrations and noise produced by roads, railways, aviation, and other ecological processes. The primary purpose of this was to reduce environmental vibration and noise.
-
Musical Acoustics
Musical acoustics is the subject of music's mechanics that is how sounds are being used to compose music. This also includes Human voice, musical equipment, and music therapy.
-
Ultrasounds
Ultrasounds are waves with a frequency higher than that of the human ear. When compared to conventional sound, there is no variation in physical attributes. Ultrasound is utilized in a wide range of applications. Ultrasonic gadgets are used to detect things and measure ranges. In physics, ultrasound imaging is applied.
-
Infrasounds
Sounds with a frequency rate of lesser than 20 Hz are considered infrasounds. Infrasonics is the study of these sounds. The observation of petroleum production beneath the earth's surface and the probability of earthquakes are two examples of these applications.
-
Vibration and Dynamics
It's the science of mechanical systems' motions and interactions with their surroundings. Vibration regulation, which serves to safeguard a building from earthquakes, and underground vibrations, which are utilized in railways, are examples of these applications.
Check More: Frequency and Wavelength
Condition for Good Acoustics
[Click Here for Sample Questions]
The conditions required for good Acoustics are as follows:
- Syllable: The syllable should be delivered loudly.
- The time between the two syllables: The previous syllable's reflection should be kept to a minimum so that the next syllable can be recognized.
- Echo: The volume of echoes that need to be adjusted should be kept to a minimum so that the sound's continuity is not interrupted.
- Hall: To reduce extended sound reflection, the building's windows should be opened and equipped with absorbent materials.
- Reverberation: The term "reverberation" refers to the sound's reflection. The sound reflection should not be too small because if it fades before reaching the ears, the sound continuity will be broken. The Dead Hall Effect is a type of situation in which sound reflection fails to function.
Also Read: Difference Between Echo and Reverberation
Applications of Acoustics
[Click Here for Sample Questions]
Acoustics could be observed in almost every area of modern civilization, particularly in the audio and noise control sectors. As a result, acoustics is used to facilitate proper sound transmission.
Applications of Acoustics
Traditionally, acoustics were just applied in industries as a noise control method. But, now it is employed in a range of sectors such as:
- Building and construction sectors
- Investigation of atmospheric and oceanic phenomena.
- Industries involved in noise reduction
- Detection of gasoline below the Earth's surface
- Detection of earthquakes
Check More: Relation between Frequency and Velocity
Acoustics Instruments
[Click Here for Sample Questions]
Any instrument can be acoustic in nature if they are having strings whether they are made of wood or brass. Some instruments which are acoustic in nature are pianos, violins, guitars, clarinets, etc.
Things to Remember
- Acoustics is defined as the science of the production of sound, its transmission, and propagation. The word ‘Acoustic’ is derived from the Greek words ‘Akoustikos’ and ‘Akoustos’, basically meaning ‘heard or audible’. An acoustician is a person who studies acoustics.
- There are various types of Acoustics such as Environmental Noise, Music Acoustics, Ultrasounds, Infrasounds, and Vibration and Dynamics.
- Acoustic Energy is defined as the energy that is related to mechanical vibrations from its constituents. The various stages of the acoustic event are Cause or Generating Mechanism, Acoustic wave propagation and Reception Effect.
- The conditions that are required for good acoustics are Syllable, the time between the two syllables, Echo, Hall, and Reverberation.
- Acoustics is now implied in a variety of sectors such as the Building and construction sectors, investigation of atmospheric and oceanic phenomena, detection of gasoline below the Earth's surface, detection of earthquakes, etc.
Also Read:
Sample Questions
Ques. What type of material/system to use to thermally isolate the sensor from a hot pipe surface with good acoustic conductivity in the region of 0.2 to 5 MHz ultrasonic sig? (3 Marks)
Ans. The sensor is developed for a maximum temperature of 130°C, whereas the pipe surface temperature varies between 200°C to 450°C depending on the application. The isolated pad must have adequate ultrasonic signal acoustic conductivity in the region of 0.2 to 5 MHz. The isolated pad should be a few mm thick. Certainly, cooling layers of the requisite dimensions could be utilized. The surface layer of the sensors might be 40x80 mm in size.
Ques. Compile a list of 3 distinctions between sound and light waves? (3 Marks)
Ans. The distinction between sound waves and light waves is given below:
Sound wave
- It moves in a longitudinal wave.
- A type of medium is required for its propagation.
- It travels at a speed of 332 propagation m/s at 0°C through the air.
Lightwave
- It travels in a transverse wave.
- Medium is not required for its propagation.
- It travels at a speed of 3 x 108 m/s through the air.
Ques. How do we keep noise pollution under control? (3 Marks)
Ans. Eliminating the roots of noise pollution is one option to minimize noise pollution. The following are some of the methods for reducing noise pollution:
- Aircraft engines, industrial machines, vehicles, and household items should all have noise-cancelling mechanisms.
- All loud activities should take place outside the residential zones. Because of the amount of noise they generate, industries should be situated away from residential areas.
- The use of televisions, music systems, and car horns should be minimized.
- To reduce the adverse effects of noise pollution, more trees should be planted.
Ques. What Is A Polar Plot and how it is used? (3 Marks)
Ans. Polar plots represent the angular variation of the sound pressure measured by the microphone in a radially symmetric view. A polar plot will indicate how the sound pressure level received by the microphone fluctuates at various angles of incidence based on the data provided. The microphone is usually placed in the centre of a 180/360-degree arc of incidence. As you walk out from the centre, the amplitude of the pressure drops. Polar plots do not indicate the frequency modulation of the recorded sound pressure and are acquired at a single frequency.
Ques. Which Microphone should we use to measure low frequency? (3 Marks)
Ans. The word "low frequency" is a descriptive term. The -3 dB point of standard 1/2" condenser test and measurement microphones is 1 Hz to 3 Hz, which is suitable for most situations. Specialized microphones have been designed that can measure frequencies as low as 0.1 Hz.
Microphones with smaller diameters usually have a higher upper-frequency level capability while microphones with larger diameters are more sensitive and suitable for lower frequencies.
Ques. If the velocity of sound in air is 340 ms-1. Calculate: (3 Marks)
a) wavelength when the frequency is 250 Hz.
b) frequency when the wavelength is 0.80 m.
Ans. Given the velocity of sound, υ = 340 m/s
- V = 250 Hz
using, υ = λ v
λ = υ/λ = 340/250 = 1.36m
- λ = 0.80
using, u = λv
λ = υ/λ = 340/0.80 = 425Hz
Ques. Demonstrate an experiment to prove that sound propagation requires a medium? (3 Marks)
Ans. Take a tumbler, which could be made of metal or glass. Check the tumbler if it is entirely dried.
Place a cell phone inside the glass. Request one of your friend to dial the number from a different phone. Keep a close watch on the mobile ring.
Curl your hands around the rim of the tumbler firmly. Occupy the gap made by your hands with your mouth. Ask your friend to call the number again. Listen to the mobile ring while sucking air from the glass.
Keep a keen eye on the glass and remove it from your mouth as soon as possible. The smaller air volume in the tumbler is likely to be attributed to the ring's smaller size. If the tumbler is devoid of air, there will be no noise. This indicates that sound must travel through a medium.
Ques. What are the types of acoustics? (4 marks)
Ans. The types of acoustics are:
- Environmental Noise: Such acoustics analyzes the vibrations and noise produced by roads, railways, aviation, and other ecological processes. The primary purpose of this was to reduce environmental vibration and noise.
- Musical Acoustics: It is the subject of music's mechanics that is how sounds are being used to compose music. This also includes Human voice, musical equipment, and music therapy.
- Ultrasounds: Ultrasounds are waves with a frequency higher than that of the human ear. When compared to conventional sound, there is no variation in physical attributes. Ultrasound is utilized in a wide range of applications. Ultrasonic gadgets are used to detect things and measure ranges. In physics, ultrasound imaging is applied.
- Infrasounds: Sounds with a frequency rate of lesser than 20 Hz are considered infrasounds. Infrasonics is the study of these sounds. The observation of petroleum production beneath the earth's surface and the probability of earthquakes are two examples of these applications.
For Latest Updates on Upcoming Board Exams, Click Here: https://t.me/class_10_12_board_updates
Also check:
Comments