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Alternating Current — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsAlternating Current3 Marks
Question
  1. What are the three basic units in communication systems? Write briefly the function of each of these.
  2. Write any three applications of the internet used in communication systems.
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Answer

Three Basic units:
Transmitter:
  • Processing & transmission of message signal.
Communication channel:
  • The link for propagating the signal from transmitter to receiver.
Receiver:
  • Extracting the message signal from the signal received by it.
Three applications of internet:
  1. Internet surfing.
  2. E-mails.
  3. E-banking.
  4. E-shopping.
  5. E-booking (e-ticketing).
  6. Social networking.

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