Waves & Secret Messages Explorer

A wave is a disturbance that carries energy from one place to another without moving the matter itself.

Think of a wave on water: the water goes up and down, but a floating leaf stays in the same spot -- the wave passes through it.

Waves carry information: voices, radio signals, and light flashes are all waves.

Sound waves are vibrations that travel through matter.

• Travel through air, water, and solid objects
• Cannot travel through empty space (vacuum)
• Speed in air: about 343 meters per second
• Your ears detect sound wave vibrations

Light waves are electromagnetic waves that can travel without matter.

• Travel through air, water, and empty space
• Blocked by opaque (non-transparent) objects
• Speed: about 300,000,000 meters per second
• Sunlight travels 150 million km to reach Earth in 8 minutes

Both sound and light waves can carry messages and information over long distances.

• Lighthouse flashes use light to warn ships
• Morse code uses short and long signals to spell words
• Dolphins use sound waves to communicate underwater
• Wi-Fi and radio use electromagnetic waves to send data