The Colour Spectrum and Locating Magnetic North

The Colour Spectrum

Light may look transparent, but it actually consists of a spectrum of colours - red, orange, yellow, green, blue, indigo and purple. Here's an experiment that demonstrates the colour spectrum.

Materials

You will need:

  • Black paper
  • Scissors
  • Tape
  • Flashlight
  • Clear plastic box
  • Mirror
  • Thick white paper

Procedure

  1. Make a small notch in the black paper and tape it to the glass part of the flashlight.
  2. Pour water into the box to the halfway point. Stand the mirror up in the water against one side of the box.
  3. Turn off the lights and focus the beam of the flashlight on the part of the mirror that's submerged. Hold a sheet of white paper so that it reflects the light. The colours of the rainbow will appear on the sheet of paper.

Locating Magnetic North

The Earth is like a great big magnet that forces all the other magnets to point to magnetic north at the top of the world. Here are some experiments that involve locating magnetic north.

  1. Observing Shadows. Take your students outside on a sunny day, around noon, and ask them to observe which way their shadows are pointing. Shadows point northward because Canada is located in the Northern Hemisphere. If we lived in the Southern Hemisphere, our shadows would point southward.
  2. Making a Compass

 Step A

Materials

You will need:

  • Bar-shaped magnet
  • Tape
  • Small plastic container
  • Bowl
  • Water
  • Stick-on labels

Procedure

  1. Tape the magnet in the middle of the small plastic container.
  2. Fill the bowl with water and float the container in the bowl.
  3. Once the container stops moving, mark the edge of the bowl with two labels opposite either end of the magnet – one for north and one for south. Proceed to step B to see which is north.

 Step B

Materials

You will need:

  • Piece of cardboard
  • Pen
  • Scissors

Procedure

  1. Cut out a circle of cardboard the same size as the opening of the small plastic container.
  2. Draw a cross on the cardboard. At each of the four points, moving clockwise, write the first letter of one of the cardinal points - N (north,) E (east), S (south), W (west).
  3. Place the cardboard on the container so that the N is opposite one of the labels. As you turn the container slightly, you can see that the magnet keeps turning back to face north. Place the N at that mark. Once the magnet stops moving, the compass will show the cardinal points.