Messages Made of Patterns
- Physics
- Ages 8–11 · Grades 3–5
- Hands-on experiment
What you’ll find out
- A signal carries information when its pattern stands for something agreed.
- Morse code and computer code both build messages from only two signals.
- Pictures can be sent as a grid of numbered squares, called pixels.
No sign-up and no real names. In the lesson you check your understanding as you read, run the experiment yourself, and practise until it sticks.
Patterns carry information
A signal carries information when its pattern stands for something. Morse code uses only two signals, a short one and a long one, and puts them together to make letters. Three short, three long, then three short spells SOS, the call for help. Lighthouses do the same trick with timing. Each one flashes its own pattern, so a sailor with a chart can tell which lighthouse it is. A flash does not mean S by itself. It means S because everyone using the code agrees.
Ones, zeros and pictures
Computers use a code with only two signals as well, written as 1 and 0, because a circuit can easily tell on from off. Letters have agreed numbers, so a whole message can travel as a long stream of ones and zeros. Pictures work the same way. Split a picture into a grid of tiny squares, called pixels, and send a number for the colour of each one. If the squares are small enough, your eye sees a smooth photograph instead of a grid.
Curriculum links: NGSS 4-PS4-3