# Day 146: Projectiles

Wednesday, 6 April 2016

Topic: projectiles launched horizontally

Here’s what it looks like when I set up a projectile problem. I like the way I can emphasize time being the one quantity that connects the two simultaneous motions.

By the way, I define projectile motion as “objects moving horizontally and vertically simultaneously through the air”. Marbles rolled off a lab table are projectiles but airplanes are not (because lift, several kids told me). What about that baseball we threw in the air two weeks ago? Yep but fun fact, kids: the horizontal velocity is just zero.

Dudes, when I walked by this desk, I was blown away by the color coordination going on in this kid’s notes:

How do I feel that this is a nearly exact copy of my version on the board? Yeah, yeah, I know it means she might not be processing the information. But I like the meaningful use of color too much to get worked up that the kid’s copying me verbatim. I think she’s processing something because fun fact: when doing examples, I stop at the givens (in green) and make the kids do all my algebra for me. So the purple work is entirely her own.