Day 88: Starting to ReconcilePosted: February 13, 2014
As we go through conceptual aspects of circular motion, students are starting to confront their misconceptions with what they think should be true based on what we’ve studied. This group was a fascinating example; they ‘knew’ that the net force should be toward the center of the circle in the yoyo problem (Problem 4 of Practice 1 in this packet, the descending part), so they tried to make the tension at an angle. They got up and in front of the class and immediately addressed their conflict, that if they draw tension sideways the net force is angled, which they didn’t think could be correct, but that it didn’t seem to make sense to have the tension angled. Discussion helped them and the rest of the class realize that centripetal force can be a component of the overall net force if the circular motion is non-uniform.