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Temperature

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This term the lecture was organized around a presentation . This helped organize the lecture. Ice water, boiling water. Putting the coconut oil in a bath of 100°C water accelerated melting to real time. Then placing the coconut oil in the ice water beaker re-solidified the oil. This provided a more vivid demonstration of the melting and solidifying temperature for coconut oil. Pouring boiling water into the 300 ml bath for the coconut oil could benefit from having gloves.  Coconut oil in the ice bath  Board notes including temperatures and heat transfer diagram. The temperature material took until 12:30, thirty minutes. This left twenty minutes for how heat is transferred and a quick once over the three laws of thermodynamics.

Hydroponic and raised bed garden

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The ethnobotany class that can verge on being a friendly mob visited the Entrepreneurship center's hydroponic facility and raised bed gardens. A Nutrient Film Technique system is the oldest system in the hydroponic facility. Produce is sold every Wednesday. A bucket system was added after the NFT system for fruiting vegetables such as green bell pepper. An aeroponic tower system was added just this year. Far more compact and space efficient than an NFt system.  Marco signs the guest register, Merryoleen strikes a pose. Merryoleen was the first to arrive. According to Welbert she arrived in the morning.  Marco and Merryoleen get ready to moisten rockwool under Welbert's supervision. Keesha, in the background,  is ever aware of the presence of cameras.  Kelarimalyanne puts on gloves to handle the rockwool. Kelarimalyanne and Lisarita moisten the rockwool in a bucket. Delaura...

5.3 50 orange 35 blue 15 white marbles

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One hundred marbles. Students blind draw a single marble. Population probability is known. Tally the sample to obtain relative frequency.  Last spring the recommendation was to move to ratio level data . Upon further thought, the ratio level data would not demonstrate the linkage between mathematically determined probabilities and statistically inferred probabilities. Ratio level data wouldn't have obvious population values.  One could use the mass of the marbles to predict a known population mean, but that is a conceptually harder system in which to explain what the probability of individual mass classes ought to be. Those weight class probabilities would be driven by an underlying normal distribution. Students would not comprehend why the predicted probability for the class bounded by the mean minus a standard deviation and the mean has a predicted probability of 34% Fifty orange marbles, thirty-five blue marbles, and fifteen white marbles sets up an easier to se...

Force of friction on a RipStik

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Trusty towed Ikaia while Trevor read the reading on the white spring scale in Newtons. Jerson and Finley walked alongside as safety officers, although Ikaia is very competent on the RipStik. Failure is always an option. The force remained the same, 15 Newtons, for both my 75 kg mass and Ikaia's 60 kg mass. This produces a slope of zero. The force of friction spring 2026 was 11 Newtons but this was the two-way average. Towing downhill requires more walking speed by the person towing and thus a higher speed for the rider. This is a less controlled situation than the slight uphill, so this was not attempted. 

Kinetic friction

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Laboratory five focused on the force of kinetic friction.  Preset was laid out between 8:00 and 8:16 The large class and dearth of slot weights, coupled with an inability to easily order replacement weights, has each group working with four unique weights. With permutations and combinatorics, this provides ten data points. Data sheets were preprinted this term. No mass balances were brought to the laboratory: the sled is treated as zero when unloaded. This generates a y-intercept for all of the groups and thus a y=mx+b regression equation for the first time this term. This also makes the weight calculations much easier.  The morning notes were brief and light. After the 8:00 section the coefficients of friction were posted to the board.  Four weight rigs were set up on the outer tables using primarily green spring scales (500 gram-force max).  The center table was set up with two grit rigs and blue spring sc...