# Day 132: Angular Momentum, Lab Practical, & Popcorn

We had a snow day yesterday. Students (and teachers!) are getting restless for spring; after seeing the grass and even a few dandelions sprout last week, it was tough to get another 18 inches of snow.

AP Physics: Angular Momentum

Students used Pivot Interactives to explore angular momentum using a collision between a marble and a block. I started by having students determine whether the location of the impact changed whether linear momentum was conserved, which lead to some great conversations. A few students needed some reminders about linear momentum, but that wasn’t surprising given I haven’t done a great job of spiraling back to earlier topics this term.

Physics: Lab Practical

I gave students some springs we haven’t worked with yet and asked them to make a graph with period on one axis where the slope could be used to find the spring constant. This was the first time I’ve had students go backwards from an equation to picking a graph to make, so it was a little tricky, but students had some great conversations about the relationships they were working with. Next year, I’d like to try to get more lab practicals that focus on graphs rather than just calculations.

Chemistry Essentials: Popcorn

Students determined the percent yield for a bag of popcorn by finding how many kernels remained unpopped. It was messy, but it gave students a nice, concrete foundation for what percent yield means. It also came up in the discussion why some of the popcorn kernels didn’t pop, which could make this lab something to come back to when students want to blame less than 100% yield on doing the lab wrong or (shudder) human error.