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Temperature, heat, and cooling curves

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The 9:30 session opened with the Eureka heat and temperature playlist .  During the video notes were transcribed from the video to the board. This included the temperatures table, something usually set aside for Wednesday during a regular term. A teapot of boiling water was already set up along with a glass jar containing melting ice. Pohnpei coconut oil was pre-positioned in the refrigerator the day before. After the playlist a brief version of the Wednesday temperature demonstration was given. The temperature list was already on the board. This was an abbreviated list compared to a regular term. A quick run through the list provided sufficient time to include coverage of relative humidity and the heat index . The Smartboard sensors provided the input data. This was reinforced using the weather service observational data .  Trishia works solo gathering cooling curves data. Eric recording data while Jonald reads the temperatures. ...

Newton's Laws of Motion and the force of friction

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The class began with an example of a lab report with formatting issues. Then the class moved outside for coverage of Newton's laws of motion. A presentation accompanied RipStik demonstrations. Summer is a time for experimentation, sometimes prompted by serendipity. Heading to the midday lab session with only minutes to spare, the thought arose, "What if the friction lab was done without scales to mass the sled? This would simplify the weight calculations. The only downside would be  y-intercept." The lab was launched without digital scales. All four groups would work on weight, no surface roughness group.  As expected, the weight calculations were much more directly obvious. Emars records data gathered by Clayton Trishia records data gathered by Eray Eric and Jonald work together to obtain data. Ruthy "Shannon"makes measurements, Mary-ellen records the days. ...

Conservation of momentum and energy

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The morning session opened with a silent Smartboard set up. Then seven diagrams were placed into the board. Without comment. Then the set up was illustrated on the center table without rolling any marbles. When asked, three students thought one marble in would yield one marble out. Rusty explores the system. Clayton also exploring the marble system. No vocabulary has been attached at this point. This summer a table was done on the board and then the students were asked to suss out the mathematical relationship. No one thought to turn to Desmos until that was suggested. One student thought the y-intercept was likely to be zero. Eventually a student suggested that slope might be one. Only then was the extension made to marbles in equals marbles out, stuff in equals stuff out, mass in equals mass out. Speed in is roughly speed out. Then a 5=5 and 3=3 example led to "therefore the products are equal."  This l...

Acceleration of a RipStik and gravity

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On Wednesday the velocity of the RipStik was a constant. Starting from velocity = distance ÷ time yields the rearranged formula distance = velocity × time. One might note that, technically speaking, velocity = Δdistance ÷ Δtime. If distance and time are not taken to be changing, velocity is not happening.  Desmos Time versus distance produces a straight line the slope of which is just the constant velocity, 0.2 m/s in the above example.  Consider what the graph looks like for time versus velocity. The velocity remains a constant 0.2 m/s. The formula distance = velocity × time is, graphically speaking, a rectangle with one side equal to the velocity and the other equal to the time. The distance is the area "under" the velocity line. That is a core idea. Consider a RipStik accelerating at 0.2 m/s each and every second. Desmos Every second the RipStik is moving faster by 0.2 meters per second. Recalling that velocity = distance ÷ time, then distance = velocity × time. So how...