Book of Phyz updates: Force and Interaction

I've updated a couple of documents and presentations in The Book of Phyz unit on Force and Motion.

1. LabPrep: Carts and Tracks. An activity focused on learning the Pasco Introductory Dynamics System. The tracks and carts are nice, but students need to spend some time to get familiar with them. Since we do several IDS-based labs across our two-year sequence, it's time well spent. Document updated.

2. Lab: Going Through the Motions. This one is focused on understanding acceleration through Pasco's Visual Accelerometer and fan attachment with the IDS. Document and presentation updated.

3. Lab: Putting the Force Before the Cart. This activity develops Newton's second law using the IDS and Visual Accelerometer. Document and presentation updated.

All can be accessed here.