Lesson 4 of 6 · Light Optics
Experiment⭐ 30 XP⚡ Spark LabDispersion and Colour
Light Optics.
🎯 Your mission
Set it up. Test it. Be amazed.
⚡ The twist
Energy never disappears — it just hides somewhere else.
Mind = Blown
🎢 You feel weightless on a roller coaster because you and the seat are falling at the same speed.
Make a hypothesis first
Before you start: which will move faster, and why?
What You'll Learn
A prism separates white light because refractive index varies slightly with wavelength — violet slows most and bends most, red least. An object looks red because it reflects red wavelengths and absorbs the rest, not because it contains red light.
Key Words
Tap a word to see its definition.
Materials Needed
- triangular prism
- ray box
- white card
- coloured filters
- coloured objects
Safety First
- Do not use direct sunlight as the source.
- Handle the prism by its faces' edges to avoid dropping it.
Steps
Read the explanation above and note the two key terms before you start.
Split a narrow beam with a prism onto white card and mark the colour order. Then view coloured objects under a red filter and record which appear black, explaining each result in terms of absorption.
Record what actually happened, including anything that did not match what you expected.
Write a conclusion that answers the question this lesson opened with, and state your uncertainty.
Check Your Understanding
Question 1
1 of 2In a prism, which colour is refracted most?
Where you see this in real life
This is why airplanes can fly and why rockets reach space.
Stretch Challenge
Try this in real life this week.
This week, find one thing in your house that turns one kind of energy into another.
For the dinner table
“Show me something at home that uses this kind of energy.”
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Dispersion and Colour
Set it up. Test it. Be amazed.
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