Visible Light
Light, Sound and Waves

Adding beams of light

Classroom Activity for 11-14 Supporting Physics Teaching

What the Activity is for

Combining colours of light.

Here you can arrange three overlapping coloured beams of light to fall onto a screen, showing the colours that arise from adding the beams together.

What to Prepare

  • A three beam projector (typically this will have three filters (red, blue and green), perhaps with mirrors to generate three separate beams from one lamp)
  • A white screen

What Happens During this Activity

Show the three beams initially overlapped, thereby producing white light. Then split them into the three primary beams, finally combining them in pairs to produce the secondary colours.

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