Physical Science: Building Again

Students spent today building the second version of their projects based on yesterday’s design. While students worked, I visited each group to grill them on how they’d used Newton’s Laws to decide on an effective design as well as the specific ways the prototype had influenced their new design.

Physics: Net Force

Students practiced some more free-body diagrams, this time also finding the net force. This included some problems finding the normal force exerted on a person in an elevator. Since my students finished quicker than I expected, I pulled up a force vs. time graph I’d saved after bringing a force sensor for a ride on our elevator, then asked my students to decide whether the elevator was moving up or down. I got really excited when I asked for a vote, and the class was pretty evenly split, thinking there may be some good debate. The first student to volunteer their explanation, however, gave such an eloquent and complete justification that no one wanted to argue with her. Fortunately, she was right 🙂

Did I take the elevator up or down?