In Light and Electricity, 7th and 8th graders are exploring surprising aspects of light that we generally take for granted.
Take a look at yourself in a mirror and note how much of yourself you can see. Now back away from the mirror a considerable distance. Do you see more or less of yourself?
Our science studio class has dived right into exploring the many surprising aspects of light, which we generally take for granted. We are exploring light from the ground up, so to speak, by connecting the ideas of waves to geometry, and building optical magic trick devices to tease out reflection and refraction. The idea of the class is to give students a short visual picture of the phenomena, and then have them build specific tools to further investigate. As a result, we build things and ask questions every day, answering some questions while leaving others open for future exploration.
Because of the abstract nature of light waves, we have been drawing analogies to mechanical waves we see around us and using them as an initial crutch to see the invisible. The students are building models of waves and investigating the behavior that is critical to detecting light, which is resonance. They have built pendulums with strings and washers, swung them around at different frequencies, and reveled when they went haywire at the resonant frequency. They then furthered this activity by building a model with rings of varying sizes, and also learned the art of nudging systems gently to coax out the phenomena they are looking for.
In a more recent class, we discussed shadows and built pinhole cameras. The first iterations didn’t work quite that well, so we spent a day looking at our designs and troubleshooting. All the ideas came from the students. From observing dim images to the reasons behind blurriness, the class was able to explain the idea of the sharpness of an image from the geometry of the light rays. One student brought up the issue of noise, in this case caused by stray light, which led to the idea of reducing it using a blackened surface. The students made predictions about the size of the image and how a big camera compared with a small one. With the cameras ready, they wore dark hoods to further isolate stray light and take a close look at faculty table lamps that had been repurposed as bizarrely shaped light sources to check if their hunches were true.
Our upcoming building activities include making retroreflectors and understanding why they work, and how they are all around us. In the process, we plan to take a quick trip to the moon and back!
-- Kaushik Basu