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Signal Definition

A signal sends messages through light or sound over distances. For example, Morse code uses flashing lights for communication.

View Lesson on Communication Over Distances
Grades K-2 VideoCommunication Over Distances player orange
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Communication Over Distances

Fun Facts

  • Traffic lights use colors to signal actions to drivers.
  • Morse code communicates letters via short and long signals of light.
  • Sirens on police cars signal an emergency with loud sound.

Why Do We Need To Know About Signal

Learning about signals helps us know how important messages get sent. Being able to communicate well is key in many areas. Signals can be things we see or hear. Signals help keep us safe, help us find our way, and let us talk to each other every day and in lots of jobs.

Think about how an ambulance’s flashing lights tell us there’s an emergency, or how Morse code can send important messages. Knowing about signals can prepare you for jobs in emergency services, transportation, and working on ships. This knowledge is useful for a bunch of different careers.

Frequently Asked Questions

How do fire trucks and police cars communicate with people?
They use sirens and flashing lights to communicate with light and sound. Their message is that there is an emergency and you should get out of the way!
What are some ways people use light to communicate over a distance?
Possible answers: Morse code, flashing lights of a car, a light house warning boats.
How did Morse code work in the video?
Each letter of the alphabet is represented by a code of short and long flashes of light.
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