Done By: Rashid Hamdan Ali Zayed Aqeel Al-Zarouni Humaid Khamess Al-Mazmi Abdulrahman Hussain

What are Sound Waves?  Sound is a mechanical wave that is an oscillation of pressure transmitted through a solid, liquid, or gas, composed of frequencies within the range of hearing and of a level sufficiently strong to be heard, or the sensation stimulated in organs of hearing by such vibrations.mechanical waveoscillation pressuresolidliquid gas frequencieslevel sufficiently strong

characteristics of Sound  Frequency, or its inverse, the period Frequency  Wavelength Wavelength  Wave number Wave number  Amplitude Amplitude  Intensity Intensity  Speed Speed  Direction Direction  Sometimes speed and direction are combined as a velocity vector; wave number and direction are combined as a wave vector.velocityvectorwave vector

Ultrasound (Ultrasonic Waves)  Ultrasound is cyclic sound pressure with a frequency greater than the upper limit of human hearing. Although this limit varies from person to person, it is approximately 20 kilohertz (20,000 hertz) in healthy, young adults and thus, 20 kHz serves as a useful lower limit in describing ultrasound. The reflection signature can reveal details about the inner structure of the medium, a property also used by animals such as bats for hunting. The most well known application of ultrasound is its use in sonography to produce pictures of fetuses in the human womb. There are a vast number of other applications as well.soundfrequencyhumanhearing kilohertz sonography

Applications of Ultrasound  Bats (to detect their preys)  To detect an unborn babies' sex  Radars  Dog whistles  Ultra sonography  Treatment of muscular pain  Detect cracks in metals

The bat Ultrasonic Location System  A short pulse of ultrasound is emitted from a transmitter (a Bat) attached to the object to be located, and we measure the times-of-flight of the pulse to receivers mounted at known points on the ceiling. The speed of sound in air is known, so we can calculate the distances from the Bat to each receiver - given three or more such distances, we have enough information to determine the 3D position of the Bat (and hence that of the object on which it is mounted).  By finding the relative positions of two or more Bats attached to an object, we can calculate its orientation. Furthermore, we can deduce some information about the direction in which a person is facing, even if they carry only a single Bat, by analysis of the pattern of receivers that detected ultrasonic signals from that transmitter, and the strength of signal they detected.

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