Lesson 6 of 6 · Light Optics
Experiment⭐ 30 XP⚡ Spark LabWhy the Sky Is Blue
Light Optics.
🎯 Your mission
Predict it first. Then prove yourself right (or wrong).
⚡ The twist
The opposite of what you expect is often what happens.
Mind = Blown
🔥 A bolt of lightning is 5 times hotter than the surface of the sun.
Make a hypothesis first
Predict: what happens if you double the force?
What You'll Learn
Air molecules scatter short wavelengths far more strongly than long ones. Blue light is therefore scattered across the whole sky while red passes through. At sunset the light travels further through the atmosphere, so even more blue is removed and the Sun looks red.
Key Words
Tap a word to see its definition.
Materials Needed
- clear tank or bottle
- water
- milk
- bright torch
- dark room
Safety First
- Keep the torch and any electrical items clear of the water.
Steps
Read the explanation above and note the two key terms before you start.
Add a few drops of milk to a tank of water and shine a torch through it. View from the side and from the far end, and record the colours you see. Add more milk to lengthen the effective path and note the shift.
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 2The sky looks blue because air scatters:
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.”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
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Send it to a parent who's looking for a 10-minute kitchen science win.
Ready?
Why the Sky Is Blue
Predict it first. Then prove yourself right (or wrong).
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