Wave Behaviors

🌊 What Happens When a Wave Hits Something?

Whether it's sound, light, water, or a radio signal, every wave is energy on the move — and when that energy runs into matter, one of a few predictable things happens. Scientists have names for each of these behaviors. Here's a quick preview of all seven — then try them out in the Wave Behavior Lab below!

📚 The Seven Wave Behaviors

🔷 Transmission

Transmission happens when a wave passes through a material and keeps going on the other side. Not every material transmits every wave — glass transmits light but blocks most sound; air transmits both sound and light easily.

• Light passing through a clear window
• Sound passing (muffled) through a wall
• Wi-Fi signals passing through the walls of your house

🪞 Reflection

Reflection happens when a wave bounces off a surface instead of passing through it. A reflected wave bounces off at the same angle it arrived — smooth, shiny surfaces like mirrors reflect light very well, while smooth hard surfaces like canyon walls reflect sound.

• Light bouncing off a mirror
• An echo bouncing off a canyon wall
• Sonar bouncing off the ocean floor to measure depth

⬛ Absorption

Absorption happens when a material soaks up a wave's energy instead of reflecting or transmitting it — that energy usually turns into a small amount of heat. Dark, soft, or dense materials tend to absorb more than shiny or light-colored ones.

• A black T-shirt absorbing sunlight and warming up
• Soundproof foam absorbing echoes in a recording studio
• Thick curtains absorbing outside noise

↗️ Refraction

Refraction happens when a wave bends because it changes speed while crossing into a new medium. Light travels slower through water and glass than through air — that change in speed is exactly what causes the bend.

• A straw looking "bent" in a glass of water
• Rainbows forming as sunlight refracts through raindrops
• Eyeglasses bending light to help you see clearly

🎛️ Polarization

Polarization happens when a filter only lets waves vibrating in one particular direction pass through, blocking the rest. Ordinary light vibrates in every direction at once — a polarizing filter narrows that down to just one.

• Polarized sunglasses cutting glare off water or snow
• 3D movie glasses using polarized light for each eye
• Camera filters that reduce reflections on glass or water

🌀 Diffraction

Diffraction happens when a wave bends and spreads out after squeezing through a narrow opening or around the edge of an obstacle. The narrower the gap compared to the wavelength, the more the wave spreads out on the other side.

• Hearing someone talk around a corner even though you can't see them
• Light spreading out after passing through a narrow slit
• Radio waves bending around hills to reach a car radio

✨ Scattering

Scattering happens when a wave bounces off many tiny particles and heads off in lots of different directions at once, instead of one clean bounce like reflection. Fine dust, water droplets, and even air molecules can all scatter waves.

• The sky looking blue because sunlight scatters off air molecules
• Sunsets looking red and orange as light scatters through more atmosphere
• Fog scattering headlight beams, making them hard to see through

📖 Wave Behavior Glossary

Transmission

A wave passing through a material and continuing on the other side.

Reflection

A wave bouncing off a surface at the same angle it arrived.

Absorption

A material soaking up a wave's energy, usually converting it to heat.

Refraction

A wave bending because its speed changes when it enters a new medium.

Polarization

Filtering a wave so only vibrations in one direction pass through.

Diffraction

A wave bending and spreading out around obstacles or through narrow gaps.

Scattering

A wave bouncing off many small particles in many different directions.

Medium

The material a wave travels through, like air, water, or glass.

Boundary

The point where one medium ends and another begins — where these behaviors happen.