Fibre Optics & Modern Light Tech
📋 What it is
Light bounces along thin glass fibres to carry internet and phone data at the speed of light.
🗣️ Coach says
Modern communication runs on light. In a fibre-optic cable, light is trapped inside a thin glass strand by total internal reflection — it bounces along, never escaping, carrying huge amounts of internet and phone data across oceans almost at the speed of light.
🧠 Memory hook
Fibre optics = light trapped in glass by total internal reflection, carrying data fast.
😂 Giggle
Why did the magnifying glass feel powerful?
It could make small problems look much bigger!
😲 Whoa!
A single hair-thin optical fibre can carry the equivalent of millions of phone calls at once — and light-filled fibres cross entire oceans on the seafloor.
✅ Quick check: How does light stay inside a fibre-optic cable instead of leaking out?
Say your answer out loud first — then reveal.
Total internal reflection — it hits the glass wall at a shallow angle and bounces back in, over and over.
Total internal reflection keeps light trapped along the fibre.
🧪 Try it! (2 minutes)
Shine a torch into a clear water bottle and let the stream pour — the light "bends" along the water, like a fibre.