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USE L3 Video Clip 2: Group discusses CQ 3-1
The group discusses CQ 3-1. Based on their model they choose C (tinsel remains spread out after + acrylic is removed) because they think that some – charges go from the can to the acrylic. Sylvia doesn't think – charges are transferred from can to acrylic since they never touch. However Devon talks about getting a shock when finger is near (but not touching) a car which supports her idea that the – charges do jump from the can to the acrylic.
USE L3 Video Clip 3: Group discusses their model after watching movie of experiment
[The students watched the movie of what happens: the tinsel returned to normal after + charged acrylic was taken away. That contradicted what the group had predicted.] The group tries to make sense of what happened in the movie. Lauren finally suggests that maybe the electrons never actually leave the can; instead they just rush off to the other side.
USE L3 Video Clip 4: Class discusses charge state of tinsel when + acrylic is held near end of can
The instructor asks the class to discuss whether they think the tinsel (when the acrylic is held near) is charged or uncharged. Several students respond including both Devon and Lauren from the group. The first student argues that after the acrylic is removed the tinsel cannot be charged. If it were charged the tinsel would be spreading out. The other students talk about the situation while the + charged acrylic is held near the end of the can.
USE L3 Video Clip 1: Group discusses model to make prediction about charged acrylic near base of uncharged electroscope