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UCF L3 Video Clip 1: Class discusses CQ 3-2
The instructor asks a student who chose C in response to CQ 3-2 to explain why that is the best answer and what the problems are with the other answers. A student has a question: "Wouldn't the outcome of B and C be the same?" Another student provides an answer and then a third student adds to that. Finally Jonathan adds a comment but seems unsure.
UCF L3 Video Clip 2: Student in class asks question about friction
A student in the class raises a question about how hard the friction force can push back if the fan cart is turned on but not moving. [The class has not explicitly discussed static friction.] He suggests that friction can only push back hard enough to balance the other force. This makes sense to him and the instructor asks if it makes sense to other people. [Not in the video: Jonathan responded to the above prompt and asked about the diagram on the first PowerPoint slide of the lesson that shows the opposing force exceeding the pushing force; thus he assumed friction could be greater. The instructor pointed out that he didn't mean to imply that the opposing force was due to friction but instead just another opposing force.] Jonathan then clarifies the situation quite nicely; that friction can never be greater than the fan force regardless of how hard the pad pushes down.
UCF L3 Video Clip 3: Group 1 discusses SQ #3
Group 1 discusses SQ #3. Vanessa thinks the friction force should be greater and others seem to acknowledge that. However Megan then wonders if the friction force were greater whether the sofa would move the other way. She thinks that is strange. The group discusses that and realizes it would never move the other way in real life but they are unsure.
UCF L3 Video Clip 4: Group 2 discusses SQ #3
Group 2 discusses SQ #3. Jonathan gives a good rationale for the force arrows being the same; Brianna says it's the same as the previous diagram. Then she mentions that the answer is justified based on what they have learned but implies that her own personal intuitions might be different.
UCF L3 Video Clip 1: Class discusses CQ 3-2