Reader Ryan writes in:
I saw the potential changes to the CED [which are happening in 2025!] in AP Physics 1 with Fluids being added as a unit. What supplies would you recommend for this unit?
Good news is, you've got a couple of years. The only substantive change in the works for P1 is to add a fluids unit to the other seven existing units. And, this change will take effect for the 2025 exam.
Fluids is nice because, well, the primary thing you need is a fluid - and water is plentiful. :-) I'm gonna have to think and decide what is worth money and what's not. I mean, Bernoulli can be demonstrated with a hose, or with a tennis ball can. You probably already have identifiable metal cylinders in your chemistry department that you can use to discuss Archimedes principle. Problem 2 on the 2010 AP Physics B exam is one I wrote based on an experiment I do - but with water, not oil. I mean, it's easy enough to do this experiment with alcohol or vegetable oil, but it's much messier to clean up.
I'm sure I'll post other ideas eventually [like this one], but nothing strikes me as a must-have like smartcarts or photogates or carts-with-tracks. I'd hold off buying stuff, and then when you see something that would make your life easier, buy it then! If you have a limited budget, don't spend anything at all on fluids, just add more smartcarts or similar.
Agreed. There aren't many must-haves. In AP Physics 2, where fluids is currently renting space, I use platform/spring scales and/or force probes (for demonstrating Archimedes principle) and pressure sensors suffice for fluid statics. Meter sticks and Smart water bottles with nice smooth-edged holes melted in place near the bottom (using an old soldering iron) work great for gathering data/graphing/linearizing/analyzing error in a Toricelli's Law lab. An air compressor is fun for the floating ping pong ball demo (Bernoulli's). Otherwise it's a pretty conveniently low-tech/inexpensive unit to outfit!
ReplyDeleteMy two labs for AP Physics 2 fluids are the old, "find the mass of a submerged object" and a plastic graduated cylinder with a hole drilled in its side near the base for projectile water purposes. The only really hard parts of fluids are if you go all in and get manometers and pumps and various things you really just don't need. ...Also if you make the mistake of spending any time at all on surface tension, which is interesting, perhaps, but just not on the list of things to do. Ditto viscosity and/or turbulence.
ReplyDeleteInteresting classic conceptual fluids question: you have a container half filled with water, with a block that half floats in the water (half is submerged, half out of the water). Oil gets poured on top, which floats on the water. What happens to the block? ...This will get quite a bit of class discussion. Students are often surprised that the oil doesn't have to get under the block in order to exert a buoyant force on it.
Any idea when the College Board will update AP Classroom to include Fluids, as we're meant to teach it this school year?
ReplyDeleteOops! Now I see it's 2025.. never mind!
ReplyDelete