kruidenier physics

Thank you!

Never more than two (unless requested by teacher for scheduling reasons).

Quick volume flow rate lab using cheap 'water squirters'. They measured starting height, distance the water travelled, and time to plunge. We split one in half to get internal radius of the chamber, they predicted radius of the opening. Fun and more accurate than I expected! #ITeachPhysics 🎢

Side by side of helium balloon floating in the middle of the air with string hanging down. In one picture the string is shorter and floating, in the other longer and a portion sits on the ground.

Simple but visually striking example of neutral buoyancy I stole from a colleague. Tie a helium balloon to a long coil of string, let it rise, then clip the string at the point it loses to contact with the ground. #ITeachPhysics

Kinematic graphs, energy bar charts, table of positions, velocities, accelerations, and net force, a FBD, and a motion tracked image of a thrown ball.

APP1 project for the week before winter break/end of 1st semester: project an object, track the motion, and create a visual presentation of the motion, force, and energy. #iTeachPhysics 🎢

Also the myriad of ways to find acceleration from x and t values is a great review and discussion... "My friend did this, but I had a completely different idea, who is right?!" "Both of you"

Final unbalanced force lab for my honors physics class- 1) derive an expression for the kinetic friction coefficient of socks on tile using only times and distances. 2) Take data and numerically solve. Required whimsy makes this a favorite activity! Mass independence always stuns. #iTeachPhysics 🎢

I have found AI usually starts off pretty decent with physics problems then goes off the rails towards the end. Though often in creative ways similar to my students!

The sound of those flying pigs is enough to drive you a little mad... I only give them a few minutes to get their data!

What other topics are you covering before 2D kinematics?

Poking around, this might be a linguistic misuse on my part... With my students I use the phrase 'in an inertial state' to mean the object/system has a constant velocity relative to the reference frame. I feel like I picked it teaching APP1, but have no specific sources 🙃

We do at the start of the year (this is for my honors class), all of these are assuming the Earth's reference frame. Unless I am misunderstanding, I would say that the jumper is an example of a non-inertial object in an inertial frame for 4 of the 5 points of analysis

I'm guessing you could set up a motion detector above the person pointed down, but unless they wore a giant flat hat it would probably be error ridden. If I wanted to have motion data I would probably motion track from video and overlay a kinematic graph.

Is the object- in this case the person jumping- in an inertial state. We did balanced force systems first, then introduced accelerating systems. We use the language of inertial and non-inertial to distinguish if the object is moving at a constant speed or changing speeds.

Screen capture of normal force vs time graph labeled which sections, then chart to fill out for each section guiding them to correct force summations.

Had students jump while standing on a force platform. They copied the normal force-time graph, identified different parts of the jumping motion, and analyzed the vertical force summation for each part. #iTeachPhysics 🎢

Me: Wow, a logarithmic scale! Fancy!
Them: wut?

Or plotting a graph!

I have that mini-rant most days. Am almost three weeks ahead of previous years and still feel behind due all the added content. Students are mostly hanging in there but it isn't as fun.

I wouldn't have fun but they want to do it every year 🤷🏻 we have 10 AP Physics sections across 1/2/Cs... So a large enough physics population for 5-20 students to find it enjoyable. Maybe check out the Young Physicists Tournament for some cool problems you could work on with an interested group.

I do most years. I let whoever is on the Physics Team organize the prep and give me the list of who is taking it, so minimal effort from me. Using previous tests to practice is useful (all on the website), and payment might be tricky depending on your district. It's fun, why not!

Spring plunger cart on angled ramp, energy demo equipment- equal height change tracks, and energy demo equipment- ramp into loop, all on desk together

Making a new energy stations lab for APP1. Have the skateboard PhET, U(s) up a ramp with spring cart, U(g) down a ramp with motion cart, marbles on equal height change tracks, and ramp to loop minimum speed. Any other 'quick' energy transfers I could add? #iTeachPhysics

Snow falling outside the window, inside a physics lab station with a modified Atwood setup.

First snowfall of the year was a nice backdrop for my honors physics N2L derivation lab. Several delightfully spontaneous conversations about road friction and driving home with students. #iTeachPhysics

I have also done an egg drop but with set materials.mine was 1/2 a paper cup (they could pick how it was split), 1 sheet of paper, 2 rubber bands, and 1/2 meter of tape. More points for higher drop height. Limiting supplies forced application physics concepts and shortened time.

Pick a weird, cool YouTube video and have them build a model based on physical principles and reasonable estimates to find some value. We just estimated the average force from an orca's tail as it tossed a harbor seal vertically into the air based on a silly video of said feat.

I have similar thoughts and slightly higher cutoffs for unit exams, would rather have them be pleasantly surprised with the AP test results

Really wishing it was 60 mph so I could do a doubling proportional comparison. BBC needs to get on board!

Sadly a birthday wish of mine was for APP1 rebalancing with lower cutoff scores. Fingers crossed for a win!

The issue is the thrust+ I got a max 0.25 N, after a few sections of use would drop to less than 0.1 N. A more talented teacher I know is playing around with a LiB insert to juice it up a bit. I love all the ideas though, having a non-component constant force opens up lots of possibilities

I found thrust by having them push the force sensor nub on the cart into a wall, and did try a equilibrium 'hover' lab but angles were really low unless batteries were brand new

To provide a constant force. The fan cart was on a horizontal track. I am using them for the first time this year, frustrated with how fast they chew through batteries. You can adjust fan motor power and- with a 3D printed attachment- angle to the track. Lots of potential once I figure them out.