January 2017

Spectrum Spinners (1/4/17)

MATERIALS:

  • White Paper or White Cardstock
  • Compact disc
  • Cup with a narrow base and wider mouth
  • Soda Bottle Cap
  • Ruler
  • Pen or Pencil
  • Permanent or Washable Markers
  • Craft Glue
  • Scissors
  • Medium-sized Marbles
  • Glue gun with Glue Sticks

INSTRUCTIONS:

  1. On a piece of white paper or cardstock, trace around the outer edge of a Compact disc using a pen or pencil. Draw a dot to mark the center of this circle.
  2. Using a Ruler, divide the circle into even wedges or ‘pie pieces’ by drawing 3-4 lines through the center-point of the circle.
  3. Optional: If you would like to divide your Spectrum Spinner into spinning rings, you should add smaller circles within the center of this larger circle. To do this, you can trace around the top of a cup, the bottom of a cup, and even around a soda bottle cap for progressively smaller and smaller circles.
  4. Using washable or permanent markers, color in the sections of your Spectrum Spinner with a variety of colors. Keep in mind that whatever colors are placed in the same ring will likely mix together when you use the Spinner!
  5. Cut out the colored circle.
  6. Glue the circle to the top of your Compact disc using craft glue. Flatten out any wrinkles or bubbles in your color wheel. Allow it to fully dry.
  7. Once your Spectrum Spinner is dry, carefully cut out the very middle of the color wheel (the part that overlaps the empty center of the Compact disc.
  8. Find an adult assistant and ask them to carefully glue a medium-sized Marble in the center of the Compact disc using hot glue. (Hold the Compact disc above the table with one hand; with the other hand add a generous ring of hot glue around the middle hole of the CD. Place the marble onto the center hole. Add more glue to the top side of the CD only to secure the marble to the disc.) The marble should sit inside of the CD’s middle without falling through, but with a small bit of the marble poking through to the bottom.
  9. Allow the hot glue to set.
  10. Place the Spectrum Spinner on a flat, empty surface. Twist the marble in the center of the Spinner to get it rotating. Try spinning it slowly at first, and build up speed each time. Observe what happens to the colors as the Spectrum Spinner goes faster. What do you see?

HOW DOES IT WORK:

Have you ever wondered how we are able to see the world around us? Or how our vision is like watching a movie? Or why things that are moving really fast seem to be blurry? It all has to do with light!

Our eyes work a lot like a high speed camera. They collect light that bounces off of objects around us in order for us to see our surroundings. And if our eyes are like a camera, then our brain is the computer that turns this light information into a photographic image. Our eyes continuously collect incoming light information, taking a ‘picture’ almost 60 times each second! However, each ‘picture’ that our eyes take is slightly different from the one before it. Our brain processes the images as quickly as it can, but the tiny differences from one picture to the next appear to us as motion. Our eyes’ frame rate (or speed of collecting individual photographs) allows our eyes to create animated ‘movies’ of the world around us.

So why does the Spectrum Spinner seem to change colors the faster it spins? The secret to this experiment to make the spinning color wheel move so quickly that our eyes cannot keep up! As the colors spin faster and faster, our eyes cannot follow the motion of each color wedge. Any two consecutive ‘pictures’ taken by our eye will be of the color spinner in a completely different orientation. Our brain tries to understand this by combining, or blurring the different colors of lights together into a secondary (or additive) color.  Below is a diagram that shows a color spinner with Red and Blue wedges, as seen in slightly different orientations. The brain would blend these images to create the color Violet as the Red and Blue spinner speeds up.

The colors on our wheel don’t actually mix together! Our brain simply perceives the new color by blurring images together!

THE MORE YOU KNOW:

Adding colors of light together is a bit different than adding together colors of paint. On the left side is a diagram showing how adding pigment (or paint) colors makes different colors. The three primary colors of pigment are Red, Blue, and Yellow. Wherever two of these primary colors overlap, you can see that the secondary colors of pigment are created (Orange, Green, and Purple). And in the very middle, where all three primary pigment colors overlap, you see a dark brown (or even black). Black is the color created when all pigment colors are mixed together!

On the right side is a diagram showing how adding colors of light makes different colors. The three primary colors of light are Red, Blue and Green! Wherever two of these primary colors overlap, you can see that the secondary colors of light are created (Yellow, Magenta, and Cyan). And in the very middle, where all three primary light colors overlap, you see a very pale (almost white) color. White is the color created when all light colors are mixed together!

pigment & light

GOING ONE STEP FURTHER:

  1. Try leaving some wedges of your color spinner white. What change do you think this might make? On the other hand, try coloring some wedges black. How will this change the Spectrum Spinner? Why?
  2. Using your knowledge of adding colors of light, try to guess what color the Spectrum Spinners below would look like:Alternate spinners
  3. Get creative with your coloring! Make a polka-dot wedge! Make an animal print wedge! How might different colors inside of the same wedge create a difference in the Spectrum Spinner?