The physics of waves howard georgi harvard university originally published by prentice hall englewood cliffs, new jersey 07632. All of the properties just discussed except the speed of sound apply only to a pure tone single frequency sound which is described by the oscillations in. Other similar properties in regard to light and sound are that light and sound can be reflected or absorbed by objects. It requires material medium for propogation of energy.
Sound propagating along the wind would bend downwards. What are the characteristics of sound waves a plus topper. The sound a guitar makes and the sound a piano makes. Those that are independent of the mass of a system, such as temperature. In most cases, these properties can be changed by changing the chemical ingredients in cases of hybrid metal. While the animals make sounds to communicate with each other. The physics of waves version date february 15, 2015.
One differentiates sound according to the frequency as infrasonic, audible sound, ultrasonic and hypersonic. Properties of metals physical and mechanical properties. Worksheets on wave properties, light and sound teaching. Properties of waves, including light and sound worked examples 1 a loudspeaker makes sound waves with a frequency of 300 hz. This worksheet is a compilation of past questions covering general wave properties, light and sound. Properties of sound goals and introduction traveling waves can be split into two broad categories based on the direction the oscillations occur compared to the direction of the waves velocity. Both sound and electromagnetic waves exhibit the doppler effect. The part of a longitudinal wave where the particles of the medium are far apart. Among the physical properties, the major is lusture, size, shape, color, density, specific gravity, finish, porosity, structure etc. Illustrate how sound is produced by vibrating objects and columns of air. What are four properties of musical sounds answers. This lesson covers types of waves, parts of wavescharacteristics, wave speed equation, terms and starts discussing em waves. This unit explains what sound is, how it travels, and some of the properties of sound, such as pitch and volume. In the first round, the group formed a solid object, with the molecules fairly close to each other.
A sound waves frequency is experienced as the waves pitch. Plan and conduct investigations to provide evidence that vibrating materials can make sound and that sound can make materials vibrate. Simple vibratory systems of this kind can differ from one. Not all of the dimensions and ccss are covered in the following activities and teachers are encouraged to address them where possible. Psychological and physical properties of sound by hubert howe. List physical factors that affect sound propagation. Pre andor postassessment harcourt science text delta science modules sound, delta science readers climb science lesson plan resources 2. Sound waves, like any kind of waves, have various features or properties. To understand this, we will explore some of the basic properties of the sound waves. Some materials allow sound pass through them very easily, especially hard rigid ones like metals. Without the sound, the voice would have been challenging to be emitted out. Speed of sound waves depends upon the properties of the medium. Vibration is the rapid to and fro motion of an object.
Pdf physical and acoustic properties of gasbearing. Musical sound properties pitch, loudness, timbre, articulation, rhythm best way to visualize the properties of sound, graph depicts change in air pressure yaxis at a particular location over time xaxis. Innovative physical science lesson plan on properties and. How to find the amplitude, period, frequency, and wavelength for a sound wave. The sound waves are heard at a higher frequency as the car approaches the students. The disturbance travels as a longitudinal wave, which has a region of condensation close together and a region of rarefaction far apart. Two of the main characteristics of sound are pitch and loudness, which in turn are determined by the frequency and amplitude of the wave, respectively. Sound propagation properties of the discretevelocity boltzmann equation article pdf available in communications in computational physics 3. A sound wave with its characteristic pattern of compressions and rarefactions is shown below. It explores how ears hear and encourages students to take care of their ears. It can be generated, moved, can do work, can dissipate over time and distance, and can carry tremendous amounts of energy.
Since sound is a longitudinal wave, it consists of regions of matter that are compact compressions and regions of matter that are loosely packed rarefactions. But sodium and potassium are soft metals and can be cut with a knife. Explain to the students that sound travels better through some mediums than others. Pdf determination of physical, acoustical, mechanical, and. Properties are considered to be either intensive or extensive. Overview of glass properties glass engineering 150. Sound properties what physical characteristic of a sound wave should be changed to change the pitch of the sound. In this section we will be looking at the basic properties of sound.
It can also be defined as a human perception of sound energy. Waves have frequencies, wavelengths, amplitudes, wave speeds, intensities, timbres and. Summarize the relationship between sound and objects of the body that vibrate eardrum and vocal cords. Speed of sound is generally greater in liquids than gases and typically fastest in solids. C both waves are transverse and matter from one place to another. The energy from the gun is transmitted through the air by a largeamplitude sound wave that causes the avalanche. Region of condensation region of rarefaction movement of a single pulse of sound 4. The speed of a sound wave in air depends upon the properties of the air, namely the. D both waves carry energy and do not need a medium to travel throug.
Human hearing lies within the range of 20hz 20,000hz. When an object or substance vibrates, it produces sound. In physics, sound is a vibration that propagates as an acoustic wave, through a transmission. Importance of sound in daily life 10 amazing uses and. Elasticity hookes law stress strain diagram elastic moduli work done in deforming a body relation between elastic constants poissons ratio expression for poissons ratio in terms of elastic constants twisting couple on a wire rigidity modulus by static. The tamber, which is the noticeable tone differences between instruments. Put your sound smarts to the test with this interactive quiz and printable worksheet regarding sound, pitch, and volume. Test your understanding and answer these questions. Because of the central role played by sound in speech communication, it is important to have a good understanding of how sound is produced, modified, and measured. Well known relation between speed of sound v, frequency of sound f, and wavelength speed of sound is a material constant depends on molecular structure, temperature, and density of material, therefore product of wavelength and frequency is constant. Sound b has a lower pitch lower frequency than sound a and is softer smaller amplitude than sound c. We assume that you have some familiarity with sine waves from trigonometry, but even if you dont, you should be able to understand some basic concepts of this explanation. Essential questions what are the four properties of waves.
Materials rubber band frequency generator with speaker procedure amplitude 1. Today were going to look at the three physical properties that sound waves have. Second grade science curriculum cumberland county schools. Learn more about the properties and types of sound in this article. Feigen, ms chicago, illinois the physical and physiologic properties of sound are described with special reference to those properties that pertain to heart sounds.
Sound, a mechanical disturbance from a state of equilibrium that propagates through an elastic material medium. Sound travels fastest through solids, slowest in gases and at an intermediate speed through liquids. A purely subjective, but unduly restrictive, definition of sound is also possible, as that which is perceived by the ear. Where the oscillations describe the motion of a single object in one direction, the wave describes the continuous, smoothly connected motions of infinitely many individual quantities, such as pressures which could be measured at each place in the room.
These waves are alternately regions of high pressure and low. Loudness is expressed in a logarithmic scale using. Depends on the temperature and the medium it is traveling through. Sound, and hence music, can be analyzed in two ways.
Second, an indirect characterization allows one to extract its nonacoustic properties i. Light reflects off smooth, shiny, flat surfaces in a regular reflection pattern. A higher frequency has a higher pitch, whereas a lower frequency has a lower pitch. Oct 02, 2015 complete lesson on wave propertiesnatures of wavesmeasuring waves with key content from aqa physics. Evaluation of the acoustic and nonacoustic properties of. Physical characteristics of sound and hearing larry p. Other materials, especially soft ones like cotton wool, absorb sound.
Examples of vibrating materials that make sound could include tuning forks and plucking a stretched string. Sound is the only main form of communication for humans and animals. Light and sound students who demonstrate understanding can. The sound waves are heard at a lower frequency as the car approaches the students. Decibel scale how much greater is the sound pressure level of a typical rock bands music 110 db than a normal conversation 50 db. Fourth grade science waves sound the following learning activities were backwards planned to facilitate the development of students knowledge and skills for mastery of these ngss performance expectations. Human speech generally falls in the range from 85 hz 1100 hz. Following are a few factors that affect the propagation of sound. A longitudinal wave that is caused by vibrations and that travels through a material medium.
All videos and handouts can be found on the koopmans onphysics website. If the atmosphere in which the sound wave is travelling is turbulent, sound waves would scatter due to velocity fluctuations of the medium. The speed of sound in air generally increases by 0. Show how physical properties of sound waves are associated with perceptual experience visual and auditory stimuli both occur in the form of waves. A sound wave moves through matter just like a longitudinal wave moves. Physical characteristics of sound and hearing sciencedirect. Pertinent definitions are given, and explanations are presented for terms used in auscultation and phonocardiography. The six properties of sound as described in music, midi, and digital audio frequency. Study 23 physcial properties of sound, sound waves, and complex waves flashcards from leslie f. Understand properties of solids and liquids and the changes they undergo. These are called electromagnetic waves or em waves. Sound travels in waves and is caused by vibrations. Echolocation is an example of a specialized sound detection system. It is compiled to meet all attainment levels, from core to extended and suitable for candidates preparing for igcse, olevel, gcse, edexel etc.
Analyzing musical sound stephen mcadams, philippe depalle and eric clarke introduction musicologists have several starting points for their work, of which the two most prominent are text and sound documents i. Pdf sound propagation properties of the discretevelocity. Stretch the rubber band so that the rubber band is only touching something at the ends. The sound waves decrease in speed as the car approaches the students. The most basic characteristics of a sound wave are pitch, loudness and tone. In the 19th century, scientists developed wave models to visualize how sound waves moved. When sound waves are represented in a waveform, we instantly notice some basic characteristics.
Unit 1 properties of waves including light and sound. The freqency f of sound is constant upon propagation, thus its wavelength. In the graph, the xaxis is the horizontal axis, and the yaxis is the vertical axis. Gcse physics p1 wave propertiesnatures of wavesmeasuring. Sound pressure is measured in decibels db on a log 10 scale relative to a reference level db 20 log 10 p 1 p r where p r is a reference pressure level a common reference pressure level is the threshold of human hearing at 1 khz, referred to as sound pressure level spl a sound with twice the spl is 6 db louder. Aug 18, 2014 the 3 physical properties of sound waves. Properties of sound bowling green state university. The waves bounce off with the angle of incidence i equal to the angle of reflection r. Some familiar properties are pressure p, temperature t, volume v, and mass m. The three most important ones for audio work are shown here. Light reflects off rough, shiny, uneven surfaces in a diffuse reflection pattern. We further accelerate the process by learning a mapping from a sound wave to object properties, and using the predicted values to initialize the inference.
A sound is any vibration wave traveling through the air or other medium which can be heard when it reaches a persons ear. Pdf 1 fundamentals of acoustics world health organization. Objectives of lesson to know that sound can be reflected, refracted, diffracted, and produces interference effects. Physical and acoustic properties of gasbearing sediments in jinhae bay, the south sea of korea article pdf available in marine georesources and geotechnology 27.
The part of a longitudinal wave where the particles of the medium are close together. A sound wave is a longitudinal wave and has all the general properties of waves. Sound can be thought of as a longitudinal wave because of the vibrations of the. Values of p, v and z for various substances air water fat muscle p kgm3 1. Physcial properties of sound, sound waves, and complex waves. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
The term pitch is used to describe our perception of frequencies within the range of human hearing. First, sound the wave is the field counterpart to oscillations of a mass on a spring. Know that sound is a wave because it can be reflected and refracted as with particles, diffraction and interference only occur with waves sound waves 2. They understood that sound is a series of compressed air, characterized by sound molecules close together, followed by rarefied air, in which the molecules are farther apart. The picture below shows a sound speaker in a cabinet with its front panel removed. The speed of sound depends upon the type of medium and its state. Its sound waves that are kinda like pressure moving at different speeds. These sound waves can only travel through a solid, liquid or gas. They rise in frequency as they get closer and lower as they move away.
Production of sound sound is produced due to the vibration of objects. Amplitudeloudness refer to how loud or soft the sound is. Oct 17, 2017 which pair of properties apply to both sound and electromagnetic waves. So take a minute and think about them, about their rate, strength and pattern. As we get older the upper range of our hearing diminishes. One aim of this chapter is to show that there are important properties of sound that cannot be. Waves that follow this pattern are called longitudinal waves.
Sound pressure is measured in decibels db on a log 10 scale relative to a reference level db 20 log 10 p 1 p r where p r is a reference pressure level a common reference pressure level is the threshold of human hearing at 1 khz, referred to as sound pressure level spl a sound. A sound wave is both the end product of the speech production mechanism and the primary source of raw material used by the listener to recover the speakers message. The wood samples from sound, moderately affected and severely affected sundri trees from three. Such properties of the metal are natural and that is determined by the formation and bonding of election. Notes on wave properties michigan state university. The tone of a sound wave can be recognized by the regularity of its vibration. This is an innovative physical science lesson plan on sound waves based on asking the right questions to students in order to explain the characteristics, properties and modes of propagation of sound waves. The waveform is a pictorial representation of the pressure variation in the air which travels as sound. The task specifically probes to determine whether students recognize that sound result from vibrations. Ncert cbse notes for class 9 science physics chapter 12 sound. We, humans, communicate verbally with spoken languages besides body languages. The objective of this lesson plan is to teach your students that they dont have to be great scientists to think of theories, just that their fundamental explanation of the theories must be. Although the two stimuli are very different in terms of composition, wave forms share similar characteristics that are especially important to our visual and auditory perceptions. Some waves do not need matter called a medium to be able to move for example, through space.
Physical properties of sound sound is energy produced by vibrating bodies, which produces a disturbance in air molecules. Sound will continue only as long as there is energy in the system to keep it going. Sonic infrasound is a sound too low for humans to hear, below 20 hertz. The fact that the sound of the gun can start an avalanche suggests that sound energy travels by waves. Bats and insects use a sound detection system known as echolocation to navigate their way through their environments. Next they will be air molecules, fairly far apart from each other. Speed of sound is generally greater in liquids than gases and. A sound is made by changes in air pressure caused by energy, like the energy you use to clap your hands. Warning signs in an avalancheprone area would include no dynamiting, gunshots, or loud noises in this area. Pdf physical properties variation of sound and top dying. Ask the students to stay in their line, but let go of each. Pdf young coconut is a popular tropical fruit featuring soft white aromatic flesh and sweet white.
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