Middle and High School … from a Montessori Point of View
These three excellent, short videos on John Snow’s life and work on cholera do a nice job of describing what makes for good science–careful observation; good notes; creative analysis of data, etc. They should make a good “spark your imagination” introduction to biological science.
They also have an excellent explanation of all the ‘lies’ and liberties they took in the making of the video.
This week I’m learning how to build an electric guitar–from scratch (or almost). Tom Singer, a professor in design and manufacturing at Sinclair Community College in Dayton, Ohio, is the lead on an NSF funded project to bring guitar building into schools.
I may have a tin ear when it comes to music, but there is quite the interest in guitar playing at the Fulton School at the moment–all the way from the elementary kids to the high schoolers–so I thought it would be a good catch-the-imagination mechanism for use in math and science.
First we got to choose a guitar body. The guitarbuilding team had a fair collection of guitar shapes for the group in the workshop to choose from. The shapes are cut from 1.75 inch thick woo. To get the elegant layered patterns you see above, they laminate about half a dozen different types of wood. This may make for beautiful guitars, but the different densities and hardnesses of the wood have to be considered when working with them. The darker colored woods in the guitar body above were much harder to shave and sand than the lighter colored material.
Note to self: Indeed, if I remember to get hold of some scrap pieces of the different woods, I can probably make up a nice density measuring project. Indeed, it would be nice to have students graph the relationship between density and hardness. Wood hardness is measured on the Janka scale. I suspect there is a positive relationship, but I’d like to see if we could determine the shape of the curve.
Not all of the guitar bodies are beautiful laminates, however. Some, of a single type of wood, are the best candidates for painting. Others are hollowed out, and can be played acoustically as well as plugged in.
Today I learned what a fretboard is. Apparently it’s a separate piece with the gradational markings that’s attached to the neck.
The necks were all of maple, if I remember correctly, but the fretboards were made of different types of wood. Each was a single piece of wood, but the wood’s hardness and affects the “brightness” of the sound produced by the guitar.
So now it’s time to sculpt and sand the body, and put all the pieces together.
For talking about migration, here’s a short video showing one day’s worth of air traffic around the world from the Zurich School of Applied Sciences. It’s pretty amazing.
NASA’s Spot the Station website tells you when and where to look to see the space station.
NASA gets dramatic. But the drama is oh so appropriate when you see what they have to do to land a rover on Mars. There are so many steps to the landing — heat shields, atmospheric friction, parachute, rockets — that it’ll be amazing if it works, and the video is a wonderful “strike the imagination” introduction to the physics of forces.
The one rotated piece represents the volta of the sonnet, the moment at which the poem pivots from exploring a dilemma to developing a resolution. Volta translates from Italian to turn in English so the physical translation of that structural device is quite literally done.
— Bert Geyer (2011).
Last year, my middle school class spent a fair amount of time looking at sonnets: pulling them apart; comparing similarities and differences; discovering their poetic form; and then each creating their own.
Bert Geyer took this type of analysis to the next step. He created a visual translation of a Petrarchan sonet using color and shape to represent the patterns of the sonnet.
The artist’s description of the piece is quite fascinating.
The varying stains at the ends of the lines indicate rhyme scheme. I chose to use the Petrarchan format–abbaabbacdcdee. Overall, every feature of the piece takes precedent from the composite structure of a sonnet (not any specific sonnet). But the piece isn’t an exact analog. My aim through this piece is to observe the nuances and complexities of translating from one medium to another. How certain features may be reproduced in another medium, albeit differently. And how translation to a new medium has limitations and new opportunities.
— Bert Geyer (2011).
I particularly appreciate that the statement so clearly demonstrates the care and effort that went into the details of the piece. The illustration that the creation of art requires just as much thought and energy as in any other field.
This should make an excellent, spark-the-imagination, addition to any discussion of sonnets. Indeed, it can also serve as a template for how to analyze different types of poetry to look for their forms. And the meaning of all the different parts should just jump out to Montessori (and any other) students who’ve used geometric symbols to diagram sentences.
It’s a glass really. Double walled, liquid suspended in air, beautiful to look at. But it really becomes a wondrous artifact of engineering when its combined with the heavy, rubber and stainless steel lid. The beauty and thermal efficacy of this tea-making system is … elegant. It’s certainly a worthy starting point for our discussion of heat, temperature and thermodynamics in general, and generates interesting questions about heat transport (convective, evaporative, conductive and radiative) and the greenhouse effect, that can be tested with relatively simple experiments.
The first, and most obvious thing my students observed was the fact that the lid prevented heat escaping. The weight of the lid confines the head space, which reduces convective heat loss above the cup and increases the vapor pressure, which reduces the amount of tea that evaporates. Evaporation is the primary way heat is lost from hot liquids, since each gram that evaporates takes 540 calories of heat with it. A simple evaporative heat loss experiment showed that about 70% of the cooling of a cup of water came from evaporation.
The second thing the students pointed out is that the double walled glass insulates, because it reduces conductive heat loss. Solid glass has a thermal conductivity of about 0.24 cal/(s.m.K) (Engineering Toolbox.com; 1 J = 0.24 calories). The conductivity of the air in the space between the walls is two orders of magnitude less at 0.0057 cal/(s.m.K). Of course, having a vacuum in the space would be even better, but it would test the strength of the glass.
Thermally, the glass falls short when it comes to radiative heat loss. A silvery coating would reflect radiated heat back into the cup much better than transparent glass. However, silica glass is relatively opaque to infra-red, which should reduce radiated heat emission. A simple experiment, comparing the cooling rates of water a glass flask wrapped in aluminum foil to one without the foil should give some indication if radiative heat loss is significant.
Finally, the glass does have a thermal advantage though, via the greenhouse effect. Because it is transparent to short, high-energy wavelengths of light, like that of sunlight, but blocks the longer wavelengths of heat energy, the glass should be able to capture some heat from sunlight. This can also be experimentally tested with a couple flasks in the sun. It would be interesting to find out how any greenhouse warming compares to the radiative heat loss through the glass walls.
Last week my students did some basic observations and came up with their own experiments. Then they learned a little about thermodyamics from reading the textbook. This week, we’ll try to get a little more quantitative with the experiments and applications of what they know, and it should be interesting to see if what they’ve learned has changed the way they observe the common objects around them.
The Auroras are a great natural phenomena that relates to elements, the structure of atoms, and ionization. They also tie into the physics of charged particles in magnetic fields. The video below provides and excellent overview and also brings up nuclear fusion and convection.
The Aurora Borealis from Per Byhring on Vimeo.
This video explains how particles originating from deep inside the core of the sun creates northern lights, also called aurora borealis, on our planet.
See an extended multimedia version of this video at forskning.no (only in Norwegian):
http://www.forskning.no/artikler/2011/april/285324———–
This video is produced by forskning.no in collaboration with the Department of Physics at the University of Oslo.
Production, animation and music: Per Byhring
Script: Arnfinn Christensen
Scientific advisors: Jøran Moen, Hanne Sigrun Byhring and Pål Brekke
Video of the northern lights: arcticlightphoto.no
Video of coronal mass ejection: NASA