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How does radio work?

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Quick answer

Radio works by encoding sound onto invisible electromagnetic waves and broadcasting them through the air. A transmitter sends the waves out; your radio's antenna catches them and converts them back into the sound you hear. Sound is converted into an electrical signal.

Step by step

  1. Sound is converted into an electrical signal.
  2. A transmitter rides that signal on electromagnetic waves.
  3. The waves travel through the air at the speed of light.
  4. Your receiver's antenna captures them and rebuilds the sound.

People also ask

How does radio send sound through the air?
It encodes the sound onto electromagnetic waves that a transmitter broadcasts and your radio receives.
What's the difference between AM and FM?
AM varies the wave's strength (amplitude); FM varies its frequency, giving clearer, higher-quality sound.
Do radio waves travel at the speed of light?
Yes — radio waves are electromagnetic, so they travel at the speed of light.