Today students had some time for open exploration using light sensors. We asked them, “What can you find out about light with this equipment?”
One of the groups had trouble getting started, and were unsure exactly what to do with their time since specific guidelines were not set. I suggested that they develop a few questions to explore by pointing the light sensor at different colors and materials which helped get them started.
After each group had made the observation that lighter colors reflect more light than darker colors, we gave them a packet that contained various materials, for example: different colored pieces of construction paper (purple, pink, red, yellow, green), a piece of aluminum foil, two pieces of wax paper, white printer paper, navy blue fabric, and a light brown paper towel. Groups decided to test the materials using the light sensor in different ways, and also organized their materials however they saw fit.
Each group wrote a reflection and presented their findings:
Group #1: inferred that the dark blue fabric absorbed more light than the black construction paper because of the difference in the material's texture. They also found that the tinfoil reflected more light than any other light colored paper, and predicted that this is because its surface is more reflective.
Group #2: inferred that white paper is most reflective, while black paper is least. They also found that the shiny side of their piece of aluminum foil was more reflective than the matte side, and that the amount of light reflected from the crinkled and smooth pieces of wax paper changed, depending on whether it was laying on a dark or light surface.
Group #3: found that the lux measurement increased as the color of paper became lighter, and decreased while measuring darker colored paper. They also pointed out that the texture of the material being measured has an effect on the graph.
Group #4: ordered their materials from the most reflection to least. They stated that their predictions were very similar to their findings, and that the wax paper reflected the most light, while the dark blue cloth reflected the least.