COMMUNICATIONS

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COMMUNICATIONS
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COMMUNICATIONS

• Elements of communication
• How does communication travel?
• Communication through sound waves

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Elements of Communication

• transmitter
• 
  receiver
• www.tecno12-18.com
• Message information sent in a communication

channel
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How does communication travel?

Sound waves
cables
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isvr.soton.ac.uk



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Communication through sound waves

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Whats a sound wave?

• A sound wave is a disturbance which travels
  through space .
• The waves carry signals from one place to another
• jdsage.com
  
  jasonmar.com
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Representation of sound waves

• They are usually represented as wavy lines

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Parts of a sound wave

• crest
  
  
• axis
• trough
• Axis the line running through the middle of the
  wave patern.
• Crest the top part of a wave
• Trough the lowest part of a wave

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Characteristics of a sound wave
Wavelength (?)
CYCLEPart of a wave that is continuously
repeated
amplitude(A)
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Amplitude (A)The distance from the axis to the
top of the crest or the bottom of the trough
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Wavelenght(?)Distance between two adjoining
crests
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FREQUENCY

• Frequency (f) number of waves per second
• Mesure of frequency Hertz(Hz)
• 
  mendonphysics2007p9.blogspot.com

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Relationship between Wavelength and Frequency

• Short wavelength high frequency.
• Long wavelenght low frequency.