Waves, Sound, and Physical Optics
It’s the new unit for ‘24-’25! I’ll admit, since I am not actually teaching AP Physics 2 to implement this unit- it is not one of my strongest units- but I LOVE pieces of it, specifically my diffraction and interference activities and the boundary behavior section of the first lecture. Due to the new lecture being added, some topics are hit twice- such as beats, but at different levels.
This lecture, previously the introduction to the optics unit, uses live demonstrations and simulations to illustrate and differentiate the boundary behaviors of the different types of waves. In the new curriculum, I would spend a little more time on polarization!
Academo Virtual Oscilliscope- I like to have this running on the board as I start class this day, if I can with me at a keyboard so they see the difference between music and noise!
Also, I am obsessed with Light and Color, here’s a playlist of videos I like to show for brain breaks during this unit! Cool Physics: Light and Color
If you can play the guitar, do it this lesson. Or invite a student to bring in theirs! A guitar, some tuning forks, and a doppler demo (speaker on a string you rotate around your head) can really improve this lecture!
The interference equations are some of the most unnecessarily complicated on the equation sheet- I say simply them for students, and encourage more memorization and application here than reliance on the sheet- it’s just basic trigonometry for the most part!
Diffraction and Interference Activities
I run this as a series of 6 activities- the first three are hands on calculations (Unknown wavelength using known diffraction grating, diffraction grating using known wavelength, and thickness of a piece of hair) that you can see pictured in the video (yay for COVID- created learning resources). The 4th is just view of an oily sink- thin film interference! The 5th and 6th use pHet’s Wave Interference Simulation to get a deeper conceptual model going!