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Showing posts from June, 2023

Ohm's Law

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SC 130 Physical Science laboratory twelve centers on Ohm's Law relating voltage, current, and resistance. The laboratory has been using equipment that dates back to the Community College of Micronesia (CCM).  With thanks to the team that supports the course at the college, the Ohm's law laboratory now uses multimeters, circuitry breadboards, and banded resistors. Here the pre-existing Ohm's law rig can be seen with the decade resistance box and a separate voltmeter and ammeter. This equipment is at least 30 years old and is likely to be around 40 years old if not older. At this point only two complete rigs can be set up using the old equipment.  One of the educational drawbacks to the CCM equipment is that the decade resistance box is not a component that is used in electronics. The decade resistance box was designed and built for classroom use. Students do not get exposed to the color band system for resistors nor do they even see a resistor. The new laboratory uses a circ

Reflection and refraction

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I went in early to do a double set up of both lecture and laboratory. I rearranged A101 moving a table from the office to handle my keyboard and mouse. In keeping with reduction in videos I went with a demonstration-only mode in the lecture session. Filling the graduated cylinder. Speakers seem to work well from back here. The ChromeOS computer was pulled from the room as part of the rearrangement. Refraction demonstration set up. Another refraction demonstration: the coin under the beaker of water.  Laser pointer.  I had to add the black plastic lid to cut down on surface reflection off of the water. The coins can be seen on the right but not the left. Well, except for the translucent plastic. I added the sandpaper to resolve the translucency issue. The final setup. As seen from the far end of the tables. Only the coins on the right can be seen. This term I forgot that a towel under the coin helps. Fortunately I had a towel in the office. The left board after the morning session, whic

The colors of light

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Summer term always feels like the term to experiment with experiments, to try variations in the curriculum. Rather than start with the Limits of Light , which is a day one activity during the regular term, I planned to start with the CD spectrograph boxes and then run Limits of Light, rather than the other way around. Experience the reality first, then the theory.  The interesting twist was that due to a local high school graduation, there were no students for the morning session. By the time of the laboratory session two students had arrived on campus.  The afternoon lab ran without the precursor video playlist on color . This is part of an attempt to reduce the number of videos as the tail end of the course is becoming too video heavy. The course has a core intent of being focused on science as the result of explorations that can be experienced. CD spectrograph What one sees with the human eye is different than what a digital camera can capture. In the above image the cyan band is m

Waves

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 The morning session was a RipStik wave on the sidewalk. I opter for four sheets this term. In a change from every previous term I swizzled downhill. I tried to hold a straight line down the centerline, but part way across the sheet I missed a beat and went off track to the left. That can be seen in the center line work above. This term I chose to lay down the center line first as a continuous straight line, rather than attempting to join the midpoints between the crests and troughs.  Only after the center line was drawn did I select a curve to trace. By sheer coincidence there were exactly four crests and four troughs on the 333 cm long poster pad paper sheets. Distract by my bobble and wobble on the board, I did not get my stopwatch shut down at 333 cm. While my watch said 3.78 seconds, I knew that was late and ran with 3 seconds. For the amplitude, which was actually the second topic covered, I picked one crest (5 cm) and the adjacent trough (8 cm), added them, and divided by two to