Waves, Light & Sound
📋 What it is
Waves carry energy without carrying matter; light and sound are both waves with key differences.
🗣️ Coach says
A wave moves ENERGY, not stuff — a ripple crosses a pond but the water stays put. Sound waves need a material to travel through (air, water) and move fairly slowly. Light waves are faster and can even cross empty space — which is how sunlight reaches us.
🧠 Memory hook
Waves move energy, not matter. Sound needs a medium; light can cross empty space.
😂 Giggle
Why did the plant fail the science test?
It couldn't photosynthesize the material fast enough!
😲 Whoa!
Light is so much faster than sound that you see lightning before you hear thunder — count the seconds between to estimate how far the storm is.
✅ Quick check: Why do you see lightning before you hear the thunder?
Say your answer out loud first — then reveal.
Light travels much faster than sound, so the flash reaches you almost instantly while the sound takes longer.
Light’s speed vastly exceeds sound’s, so it arrives first.
🧪 Try it! (2 minutes)
Watch someone clap far away (a field, a gym). You see the clap before you hear it — light beats sound.