Science Fair Projects
physicsmedium elementary 3 days

Rainbow Reflection: Light and Water

In this project, students will create rainbows to explore how light refracts through water. By using a glass of water and a flashlight, students will study how different angles make different rainbow patterns.

Rainbow Reflection: Light and Water

Hypothesis

If the angle of light entering the water changes, then the position and size of the rainbow will change due to varying refraction angles.

Materials Needed

Glass of water1Buy
Flashlight1Buy
White paper1Buy
Protractor1Buy
Marker1Buy
Tape1Buy
Ruler1Buy
Notebook1Buy

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Step-by-Step Procedure

  1. 1

    Fill a glass with water almost to the top.

  2. 2

    Tape a piece of white paper to a wall to serve as the screen.

  3. 3

    Shine a flashlight at the glass of water at a 45-degree angle.

  4. 4

    Look for a rainbow pattern on the paper.

  5. 5

    Mark the rainbow's position with a marker.

  6. 6

    Change the angle of the light with a protractor.

  7. 7

    Observe and mark changes in the rainbow's position.

  8. 8

    Record observations and note any differences.

  9. 9

    Repeat with different angles to see a variety of patterns.

  10. 10

    Analyze changes in rainbow size and position.

  11. 11

    Clean up after completing the experiment.

Expected Results

Different light angles will create varied rainbow patterns, demonstrating how refraction angles affect light dispersion. A noticeable change in the size and position of rainbows is expected with different angles.

Variables

Independent Variable

Angle of light entering the water

Dependent Variable

Rainbow position and size

Controlled Variables

Water level in glass, Distance from paper, Light intensity

Safety Notes

Avoid shining the flashlight directly into anyone's eyes and handle the glass with care.

Presentation Tips

  • Use diagrams to explain how light refraction creates rainbows.

  • Show before and after images of different light angles.

  • Include a video clip of the rainbow formation process.

Frequently Asked Questions

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