Days 37-40: Unbalanced Forces

This week was a little funny because we had Tuesday off for elections.

On Monday, I gave a quiz over unbalanced forces that didn’t go as well as I’d hoped. The big thing students seemed to struggle with was sketching and using free-body diagrams and vector addition diagrams. I decided to put off starting momentum to spend a little extra time working on force diagrams. We started with a card sort with unbalanced force diagrams. Including the motion maps gave me a chance to emphasize the net force is in the same direction as the acceleration, which I hadn’t done a great job of before. This card sort also includes two sets of similar scenarios, which lead to some good conversation comparing and contrasting the similar scenarios. After the card sort, one student told me that she has found card sorts in general to be a really useful tool in helping to visualize what diagrams should look like. I realized one of the benefits of card sorts is they students the visual they are after when they ask me to do example problems on the board, but kept the bulk of the sensemaking on students. We have a lot of card sorts made for our physics courses, but I don’t use them consistently in AP in an effort to keep to a fast-moving pace. This week was a good reminder that it is worth it to make time for card sorts.

After the card sort, we moved into doing some problems, both calculations and conceptual, and students were much more confident and doing much better than earlier in the week.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s