Wednesday, June 01, 2011

Seventy-five cents never went so far

I end the Physics 1 year with light and wave optics. Ray optics has been bumped to AP Physics 2. This helps to forestall the post-CST and post-AP doldrums that might otherwise take root. By the way, when students complain they can't do this or that because they suffer from Senioritis, I remind them that Senioritis is the disease, physics is the cure, and me? I'm the doctor!

Anyway, we get to rainbows, mirages, blue skies, 3-D movies and more during this season, so it's not so bad for anyone.

When we talk about diffraction, we end up doing an activity called "Diffraction in Action." (I know, too easy.) The activity ends with a pair of "rainbow glasses" being given to each student. Their experiences in the activity to this point allow them to see the glasses as crossed diffraction gratings.

But you'd think the Candyman had come to the room with delicious treats for the little boys and girls. Be prepared for squeals of delight and proclamations that this is the coolest thing ever and that they'll never take the glasses off.

To push the merriment over the top, I ask them to don the glasses and look toward my camera in the front of the room. When the flash pops, their collective shrieks are enough to provoke angry calls from the bowling alley, complaining about the noise we're making.

Worry not about any complaints from colleagues about the distraction that bespectacled students were in their classes. It's for science!

Of course, rainbow glasses don't grow on trees. You have to order them and pay for them. I get mine from Arbor Scientific for $0.75 each (volume pricing), so I can set up all my students for about $100. I've never been denied reimbursement from whichever funding source I've asked.

Blog of Phyz readers already know I'm a sucker for activities that get jaded high school seniors to act like elementary students--if even only for a little while. This active/giveaway meets that criterion with happiness to spare.

Diffraction in Action (PDF)
Diffraction in Action Answers (PDF)


Anonymous said...

I always take my kids on a "field trip" up and down the halls as they wear their glasses and we look at the various emission spectra from the many different types of light sources installed around the school. We compare these to the spectrum from incandescent bulbs as well as from reflections outside of sunlight (don't look at the sun!).

It's particularly nice to parade the kids past any observant administrators as they have their rainbow specs on!

Dean Baird said...

^ I like it! I have an old incandescent showcase bulb, a CFL, and LED sources for the students to gave upon, but I like the idea of going outside and being seen, a whole class in rainbow specs.

Remember to tell them to keep the glasses handy for Independence Day fireworks displays.