Showing posts from June, 2013

Heat Conductivity





Elmihra, Tina, Rose Ann, Risenta

From longitude to spectra

Finding Binky went rather well on a Wednesday morning. In the afternoon I opted to deploy the redesigned laboratory seven. The new design once again simplifies a laboratory that has continued to remain confusing for the students. The redesign puts a linear relationship into the core of the laboratory, including a graph.

In retrospect I should have simply subtracted the starting longitude. The class walked east on a line of latitude. Not "zeroing" the longitude data leads to a large and rather meaningless y-intercept. Future runs should deduct the starting longitude when walking along a line of latitude.

I chose to roll the surveyor's wheel while the students held the GPS units. The surveyor's wheel is not zeroing properly any longer and I did not want to potentially introduce errors due to misreading the surveyor's wheel counter. Every 100 feet I had the students report their longitude value. These distances were logged at "30 meters" rather than the 30…

Trigonometry via constructive geometry and SVG

This is a series of screenshots primarily for the benefit of the students in the course this summer.

I began the unit by rolling a large wheel, keeping track of both the linear distance and dividing by the radius to produce an angular measure.

The next day I moved into constructive geometry and SVG diagrams as a way to deliver the basic trignometric functions.

The goal was to draw a square circumscribed in a circle using SVG.

The next day the focus shifted from 45 degrees to a 30-60-90 triangle via trying to inscribe an equilateral triangle in a circle using SVG.

The homework was to generate the two triangles seen in the lower right corner above. The solutions are worked out below.

Finding Binky


Early morning at the hide.

Binky is down in the razor grass.

On a slope in the bush.

Binky coordinates

Michael and Rockson


Mackleen and Elmihra


Tina and Rose Ann

Rose Ann up slope, Mackleen and Elmihra down slope


Rockson, Tina, Mackleen, and Elmihra

Rockson. Mackleen and Elmihra in the background. Far down the valley, Michael.

Rockson gets Binky!


After a brief mention of the formula for momentum, I moved to cover Newton's three laws as formulated from a momentum perspective. Momentum unites the first two laws nicely into variations of the same formula.

I rearranged the tables in A101 and rode my RipStik while a ball balanced loosely in my outstretched hand. I collided with a table on one side of the room, and the ball kept on going. Not as vivid as the outdoor demo I did last spring under the solar panels. The greater speed made a lot of difference.

Then I used the new clothes line rope to hold 8 kg up. I used this to pull me. The 50 cm drop that the table top provided was insufficient to gain much speed. Not much better than 65 cm/s². Still, that provided the numbers I needed to work out what my acceleration must have been. Note that measuring speed post-acceleration, while not ideal, is far easier than timing the acceleration directly. One is rather busy getting accelerated, thoughts of timing are secondary.

The gear us…