Free PDFGrade 4 · Science · 35 min
Refraction code challenge
Write a word backwards, look through a jar of water and read it the right way.
I can explain how a jar of water bends light and flips a picture from left to right.
A science experiment video with a free worksheet and answer key for teachers
About the video
In the video a word written backwards reads correctly when seen through a jar of water. At home your child writes TOY and YOT, places the paper 15 cm behind a full jar, then tests BED written backwards and 4 words of their own.
The round jar works like a lens, so light from the left and right sides of the paper crosses over and the order of the letters flips back. Every letter is also mirrored, so only words made of symmetric letters such as A, H, I, M, O, T, U, V, W, X and Y read correctly.
What your child learns
- Explain how a curved jar of water flips left and right
- Find letters with a vertical line of symmetry
- Predict and test which words will work
What's on the worksheet
- 1Predict first
- 2Record your tests
- 3What did you see?
- 4The science behind it
- 5Sort the letters
- 6Key words
- 7Code breaker
- 8True or false
- 9Explain it
You need
1 round glass jar about 8 cm wide with a lid, about 500 ml water (enough to fill the jar to the top), 2 sheets of white paper, 1 black marker, 2 books to lean the paper against.
Tip for the adult
Before testing their own words, ask your child to check each letter for a vertical line of symmetry and predict whether the word will work.
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