Underwater Acoustics

2136 Words5 Pages
bulb-icon

Recommended: Literature review of underwater wireless communication

My Communications coursework will be on non-radio communications. My

chosen topic is underwater acoustics. The applications of underwater

acoustics and their advantages and disadvantages will be studied.

All forms of non-radio communications are based on waves. Waves are

generally a disturbance in a surface, transferring energy from A to B.

Waves can be mechanical vibrations travel through a medium. For

example: water, sound. These waves are called mechanical waves.

Progressive waves are created from a point and energy is distributed

to the surroundings. For example: dropping a pebble in the middle of a

pond causes energy to be distributed outwards. All waves can be

classed into two categories:

* Transverse waves: In Transverse waves the direction of the

particle movement is perpendicular to the direction of the wave.

[IMAGE]

[IMAGE]

* Longitudinal waves: The particles in longitudinal waves travel in

the same direction as the direction of the wave.

[IMAGE]

[IMAGE][IMAGE]Waves that can travel underwater without getting too

distorted are used for comunicating underwater. Sound waves fill this

criteria as they can travel long distances without getting distored

too much. Sound waves are longitudnal and mechanical waves. They are

longitudinal because when they travel they create an area of

compression and then rarefractions within the air. A sound wave, like

any other wave is introduced into a medium by a vibrating object. The

motion of the particles in the medium in which a sound wave vibrates

back and forth is measured by the frequency. The frequency of a wave

is measured as the number of complete back-and-forth vibrations of a

particle of the medium per second. Unit of frequency is Hertz (Hz).

The frequency of a wave can be altered by increasing the number of

vibrations per second. [IMAGE]Increasing the frequency, increases the

pitch of the wave. Any sound that can heard by a human ear is called

an infrasound (20Hz to 20000Hz). Above this range the sound is known

Show More
Related

  • Analysis Of An Ocean Apart A World Away

    1102 Words  | 3 Pages

    One of the greater messages conveyed through An Ocean Apart, A World Away, pertains to the eradication of sexism, encouraging equality between all genders, and re-establishing the independence of women in many cultures. The author demonstrates the struggles of one individual assimilating into a foreign culture. The difference between the Chinese and American culture is evident as are the attempts of the main character to assimilate, and adapt to his/her new surroundings. The novel compares the stereotypes women face in both the Chinese and American culture and clearly regards it as an issue. An Ocean Apart, A World Away is a unique story with an important message, providing great insight into the history of China while maintaining a subtle sense of humour to keep the story entertaining. It also has a strong female protagonist but failed to successfully develop secondary characters. Other female characters could have aided the story in giving a stronger message as well as creating a more interesting plot. The plot lacked many details during the events, causing the plot to seem rushed. Although the story is lacking in some aspects, readers will find themselves fully engrossed into the daily lives of Chinese women during the early 1900s.

    Read More

  • Steven Spielberg's Use Of Sound In Jaws

    721 Words  | 2 Pages

    Subjective sounds are sounds that do not originate from the environment but can work well to strengthen pacing, story or mood. They can be sounds that the character cannot hear or interact with but instead affect the viewer. Subjective music could be used as a way to create contrast, for example, with typically happy music set against a sad scene.

    Read More

  • Physics of Personal Watercraft

    856 Words  | 2 Pages

    Personal Watercrafts or "jet skis" are basically Personal Watercraft (PWC) are basically small inboard boats able to travel at high speeds due to large amounts of power and very light weight. Alomst all PWC's are under 600 lbs and most of todays PWC's have at least 90 hp.Not only are PWC's some of the fastest water vehicles they are also some of the most maneuverable water vehicles. This is because PWC's propultion is based on a jet that also is it's turning mechanism. When the driver turns the handlebars the jet (via cables) turns in the direction of the handlebars so the stern is pushed in the opposite direction. This allows the driver to turn at a much tighter angle than traditional boats with keels and rudders.The main drawback to this maneuverability is the fact that if there is no thrust coming from the engine the ability to turn is effictively zero meaning that anytime the driver presses the kill switch (a large red button) they lose all ability to steer. This is extremely dangerous whenever an inexperienced person may drive the PWC back to dock or into shore. PWC's have no brakes and have no ablilty to stop other than turning around. They have an extremely efficient ability to hydroplane (when most of the PWC is above water) and it takes most PWC's a few hundred feet to come to a stop after being at full throttle. This is because 600 lbs + a rider is traveling at a very high speed with only minimal friction to slow them down (since PWC's are made to travel with very little friction).

    Read More

  • Relationship Between Music And Perception

    1660 Words  | 4 Pages

    Most people are familiar with the word "music", however they barely consider the definition of it. After carefully think, everyone has their own opinions on this term and it is hard to have an uniform criterion of music sounds. According to the text book, Michael B. Bakan states five propositions to define the music. The first one is about the tone and the second one talks about the music is organized in some way. The next two are claims that music is human organized and a product of human intention and perception. The last proposition argues music cannot separate from Western culture. Among these propositions, I think the music is a product of human intention and perception is most interesting and worth to discuss. So I assert that the most

    Read More

  • The Inner Workings of Guitars

    669 Words  | 2 Pages

    At any point in the air near the source of sound, the molecules are moving backwards and forwards, and the air pressure varies up and down by very small amounts. The number of vibrations per second is called the frequency which is measured in cycles per second or Hertz (Hz). The pitch of a note is almost entirely determined by the frequency: high frequency for high pitch and low for low .

    Read More

  • The Effect of Underwater Acoustics on Whales

    1658 Words  | 4 Pages

    The Effect of Underwater Acoustics on Whales Whales utilize acoustic frequencies to communicate underwater. If the whales are unable to communicate their bi-annual migration can become perilous. Man-made low frequency sonarcan prevent whales from producing soundand sometimes causes them to take alternate routes. When the whales try to avoid the sonar they are in danger of running ashore and perishing after being beached. Introduction: Twice a year, around the months of December and May, populations of gray whales migrate from Mexico to Alaska.

    Read More

  • The Physics of Ultrasound

    892 Words  | 2 Pages

    Ultrasound is sound waves that have a frequency above human audible. (Ultrasound Physics and Instrument 111). With a shorter wavelength than audible sound, these waves can be directed into a narrow beam that is used in imaging soft tissues. As with audible sound waves, ultrasound waves must have a medium in which to travel and are subject to interference. In addition, much like light rays, they can be reflected, refracted, and focused.

    Read More

  • H.S. Level - SOund And Light Waves

    490 Words  | 1 Pages

    momentum transfer when air molecules collide. Our ‘subjective impression’ about the frequency of a sound is called pitch. High pitch has high vibration frequency, while low pitch has a low vibration frequency. A pure musical tone consists of a single pitch or frequency. However, most musical tones are “complex summations” of various pure frequencies - one characteristic frequency, called the fundamental, and a series of overtones or harmonics Younger people can usually hear pitches with frequencies from about 20 hertz (infrasonic) to 20,000 (ultrasonic) hertz. We can’t hear above 20,000 hertz or below 20 hertz (ultra and infrasonic waves).

    Read More

  • The Physics of a Guitar

    975 Words  | 2 Pages

    The vibration of the strings of a guitar causes the sound wave, but is not actually what you are hearing. The amplification of the sound wave is what is actually heard. The differences in the tension of the stings and the mass of the strings affect the pitch of the sound produced. The ends of each string are nodes, or where the wave does not travel from its initial position. The note you hear from the string is actually the first harmonic of the wave; other harmonics created when plucking a string form the undertones and overtones of a note. The waves on a guitar string are transverse waves, meaning they travel perpendicular to the original position. The waves are also standing waves, because they remain in the same position.

    Read More

  • waves

    1042 Words  | 3 Pages

    The frequency f of the wave is the number of wavelengths that pass each second.

    Read More

  • Hearing Tests

    1340 Words  | 3 Pages

    as Hertz (Hz). The sounds of speech are in the range of 250 Hz to 4000

    Read More

  • Physics of Submarines

    2080 Words  | 5 Pages

    Most people have some sort of familiarity with submarine crafts; most of which are most likely related to the navy. This is a very accurate depiction of submarines, as they are primarily used for this, however, they are used in areas of scientific research as well. The purpose of this web page is to go into the history of the submarine to see how it has developed over time. We will also look at how a submarine works, from a physics standpoint.

    Read More

  • Acoustics in Music

    508 Words  | 2 Pages

    Through out the history of music, acoustics have played a major role. After all if it were not for acoustics the quality of sound that we know today would not exist. The word acoustics comes from the Greek word akouein, which means, “to hear”(Encarta Encyclopedia). Since music has to be heard in most cases for enjoyment, acoustics obviously take on a very important role in the pleasure that music brings to the ear. Acoustical architecture and design are two key elements in the way music sounds. For example, an electric guitar played in a concert hall would sound very different compared to the sound produced in a small room. These differences can be explained by the acoustical design of the room and the reverb created by both the instrument and the room in which it is played. These differences signify the importance of acoustics in music.

    Read More

  • Acoustics Essay

    1774 Words  | 4 Pages

    Acoustics is a science that deals with the study of sound. It is known to be one of the branches of physics; studying oscillations and sound waves from the lowest to high frequencies. Acoustics is known to be one of the oldest sciences, and dates back to ancient times as people had the need to understand the nature of speech and hearing. The main reason acoustics was discovered and is one of the oldest sciences is because of the need for the knowledge of the sounds of music and musical instruments. Pythagoras, an ancient mathematician, was the first person to ever find out that tone height corresponds to the length of the sting or tube. While Aristotle, Pythagoras apprentice at the time, helped more to explain that an echo is created as the sound reflection from obstacles.

    Read More

  • Radio Waves

    826 Words  | 2 Pages

    waves are further divided into two groups or bands such as very low frequency (

    Read More

More about Underwater Acoustics

Open Document