Rough Science

My son has a 2 week break from his Great Books & Latin courses so we've been catching up on science labs. I'm beginning to think that like the need to teach practical theology within the context of our post-modern world, there is also a need to teach science recognizing that we live in a post-modern world.

One common mistake of today's post-modern man or woman is realizing we often know less than we really think we know. For the post-modern science student, the ignorance may be even greater because they lack enough world experience to see how much occurs without a carefully designed lesson plan. When we memorize a list or table of facts, do we really know it? So what is it that we do know, and what is it that we don't?

One nice discovery on my search for links to complement our Fizz, Bubble, and Flash experiments, was the Rough Science science reality show. If you are a Netflix subscriber, you can stream these episodes any time for free. A team of scientists (chemist, physicist, biologist) is dropped in a deserted area with few materials and a challenge to design, make, or find something in the surrounding terrain. How many of us can do this? Maybe we need to think more about our science and get out of the printed page. The first episode we watched challenged scientists to find gold in a gold mining area, purify it and quantitate it using only materials they could find in deserted saw mill.

The experiments we tinkered with this week included Electrolysis of Water using a 9 volt battery, water, and copper wires. The Rough Science team washing using electroysis to make silver iodide so that they could make a camera.



To top off our electrolysis learning we also watched this homemade Exploding Hydrogen video. It was pretty good! Even the outtakes!
Some Rough Science Challenges
Make Your Own Compass, Sea Water Batteries, Silver Iodide via Electrolysis for Camera

Ancient Warfare: Medieval Siege Weapons

Siege weapons were an essential feature of medieval warfare. At home, catapults can be made with popsicle sticks or a plastic spoon and rubber band. Here's a page of Lego trebuchets and what looks to be a simple Lego catapult. Here's instructions for a K'nex trebuchet. Nova's medieval siege site is here.

If you have Shockwave, you can play the game Destroy the Castle, but you must adjust the stone ball weight, sling length, counterweight, distance from the castle, and wheels in order to use the trebuchet effectively.

The trebuchet must have been a scary weapon. More detail about its operation can be studied at Trebuchet Physics or History of the Trebuchet.



To see a large one in action (tossing pianos or a car), check out this trebuchet video at Youtube.com ...

At home, it might be easier to toss marshmellows or ping pong balls. You can build a paper castle or medieval town by printing up these cool templates. Print up battle-specific paper medieval knights here.

Classical Science Alive: Archimedes Vindicated!

In 212 B.C. ancient Greek and Roman historians wrote that Archimedes used a burning glass to set Roman ships aflame in the Battle of Syracuse. Over the centuries, many groups have attempted to repeat Archimedes' achievement, but failed. Many believed he couldn't have done it (one of the most recent naysayers being the TV hosts of Mythbusters), but persistent against-the-odds students and teachers at MIT finally proved Archimedes could have torched the ships.

Using this sketch model, the course instructor concluded it would be possible. 95% of the class thought it unfeasible, 5% thought, well maybe....

The rest (as they say) is history: "Open, sustaining flame occurred less than 10 minutes after the sun was in a clear patch of sky!" For more on this, including answers to ponderables such why the boats and not the sails might have been set on fire, check out these Archimedes Death Ray FAQs

References:
Archimedes Death Ray

Technorati tags: classical education, classical science, history of science, ancient Greeks, Archimedes, education, engineering

Classics Physics Alive: New Acoustic Discoveries in Ancient Greek Theatres

In a recent article from Nature, researchers at Georgia Tech figured out the science behind the magnificent theatre of Epidaurus. For more detailed, info, click here. it turns out the answer is not from simply an optimal amplification of human frequency pitches, but also careful positioning of the stepped rows of seats to reduce low frequency background noise. Very cool

Excerpt: "They calculate that this structure is perfectly shaped to act as an acoustic filter, suppressing low-frequency sound — the major component of background noise — while passing on the high frequencies of performers' voices...In the first century BC the Roman authority on architecture, Vitruvius, implied that his predecessors knew very well how to design a theatre to emphasize the human voice. "By the rules of mathematics and the method of music," he wrote, "they sought to make the voices from the stage rise more clearly and sweetly to the spectators' ears... by the arrangement of theatres in accordance with the science of harmony, the ancients increased the power of the voice."


ARLT :: Why the Greeks could hear plays from the back row
Structure of the Greek Theatre
The Architecture of Acoustic Control (Modern)
Wired: Scientists Study Sacred Sounds / Church Acoustics

Ancient Greeks: Thales - Scientist, mathematician, philosopher, businessman

Thales of Miletus is often referred to as the father of science, the father of philosophy, and the father of geometry. He was a very clever man, and sought to understand the world through a study of its patterns, rejecting explanations from mythology.

We just discovered Julie Diggins' String, Straight-Edge, and Shadow, and here you can read its Thales Chapter. Among Thales' apparent accomplishments: predicting an eclipse in 585 B.C., successfully predicting a bountiful harvest of olives after several bad seasons (he was certain, he also cornered the market on olive presses beforehand, and made a great deal of money), measuring the height of Egyptian pyramids by "shadow reckoning", a strategy for measuring the distance of a ship at sea, five propositions (with proofs) of plane geometry, a theory of earthquakes (movement of land because it floated on water).













Of course, Thales was also wrong about many things (for instance, he thought all things were composed of water and that magnets (lodestones) had souls), but he inspired many generations of scientists, mathematicians, and philosophers to look for the patterns, rules, and relationships that existed in the natural world.

References:
Math Story / Lesson: On Thales
Wikipedia: Thales
Thales at the Internet Encyclopedia of Philosophy
The Life and Accomplishments of Thales of Miletus
Ancient Greeks

Classical Thinking in Physics and Newton's Laws of Motion

The discovery of the Newton's Laws of Motion provide many insights into how scientific discovery occurs - there are experiments and observations, consideration of unknown or untested variables in the experimental observations, theories knitted together from results and analogies in other systems, more experiments and use of different experimental paradigms, and finally discussions (and often disagreements) with others until one arrives at a consensus.

It was Aristotle who first noticed that masses of heavier weight tended to move more quickly in proportion to their size. This didn't make sense to Galileo Galilei, though, because he knew that projectiles like cannons didn't move in straight lines, but rather in straight curves. There has been a popular story (perhaps perpetuated by Galileo's biographer) that Galileo dropped two canon balls (one 10 times heavier than the other) from the Leaning Tower of Pisa to refute this law of Aristotle. There still remains some controversy over whether Galileo was actually able to show this, but he did try experiments using inclined planes (rolling balls down planes at different heights) to better control for the rates of acceleration and quantitate his results (in a vacuum or no air resistance), items of different mass should fall at the same rate. A page from one of his notebooks can be seen below.



The year Galileo died was 1642, the same year that Isaac Newton was born. Newton's great insight was to realize that a single law might be able to explain an apple falling from a tree, the curving movement of a cannon, and motions of the planets.

Putting his observations with the concept of Universal Gravitation, Newton imagined that if a cannonball were shot horizontally and fast enough from an iman imagined mountaintop, then it might actually orbit the earth. For an animation of Newton's cannon on a mountain, click here



Newton - What Really Happened with the Apple
PBS: Galileo's Experiments
The Galileo Controversy
Galileo's Notes on Motion

Classical Science: Telling Time with the Sun

Time to run outside in the sun!

For a simple animation of how shadows vary with time and position of the sun, click here. The animation here shows you how to estimate the size of a very large object (like the Statue of Liberty or T Rex) by comparing shadows.

When Isaac Newton was a boy, he was interested in studying the patterns of how shadows moved. He eventually constructed many sundials around his house and could tell the time just by looking at the placement of shadows.

For a good background on telling the time by the sun, and a print-out template for one to make yourself, click on this NASA site. You'll have to determine your latitude before you can use the sundial accurately so that you can factor in the tilt of the earth and its curvature. There are many beautiful sundial pictures at Wikipedia.

Another device an ancient Roman could use was an horologium ex aqua, or water clock - that displayed the month and hour on a column of water. For more on how ancient Romans kept time, check here.

If you're wondering how a person in the Middle Ages might have been able to tell the time at night, they could have used a Star Clock that uses the pointers of the Big Dipper.

Technorati tags: classical education, science, astronomy, sundials

Classical Homeschooling: Backing Our Way into Physics

I want to teach my kids to be good natural scientists. Physics always seemed to be a natural science to introduce early (even toddlers negotiate their physical world), but it's easier wished than done.

I remember Richard Feynman's writing about how his father first told him about physics principles from The Pleasure of Finding Things Out, " said, 'Say Pop, I noticed something: When I pull the wagon the ball rolls to the back of the wagon, and when I'm pulling it along and I suddenly stop, the ball rolls to the front of the wagon," and I says, 'why is that?' And he said, 'That nobody knows,' he said. 'The general principle is that things that are moving try to keep on moving and things that are standing still tend to stand still unless you push on them hard.' And he says, 'This tendency is called inertia but nobody knows why it's true.'" I like that approach because it gives knowledge with an appreciation for what also is unknown. But the problem is me. I also wish I knew as much about Nature as Anna Comstock (Handbook of Nature Study, but our natural teaching moments were more likely to be planned or science-lite, relying on what knowledge I happened to have available without looking it up in a book.

Physics is a tricky subject to teach for tweens or middle school students because it doesn't have to be as complex or rigorous as high school or college prep physics, but it also deserves more than elementary school level explanations. I had started off this year with the high school Conceptual Physics book, and we even spent some time with Conceptual Physical Sciences, but although our son could read the chapters and answer the questions, it wasn't helping him look at his natural surroundings more thoughtfully or think like a scientist. And it seemed a lot like work, rather than something that was intriguing or fun.

Recently we found this delightful site that has free online Classical Physics demonstrations. It's not enough to be a stand-alone curriculum, but it terrific for bring back the fun.

Though we covered Newton's Laws of Motion, we're now revisiting what we've learned, so that understand more about the historical context that drove Newton connect ideas about the movement of the planets, with movement on earth. In order to answer his questions in a specific way, had had to develop a new branch of mathematics (calculus) to test hypotheses about what laws could predict movement.

Newton's laws would allow others to design rockets, spaceships, and rollercoasters, predict the movements of golf balls, fluids, and neutrons in a nuclear reactor. As we collect links and for study notes, we'll post them on our blog.

I'm much happier with our current track in physics because I can see our children's curiosity and excitement returning, and they're getting a better experience for what the practice of science is - observing carefully, questioning, hypothesizing, making conclusions, and then recognizing what remains unknown.

BTW, the beautiful pictures above are from that wonderful MIT physicist and teacher, Harold Edgerton, who was able to stop time and provide surprising insights into the behaviors that previously were too fast to study.

Edgerton Golf Picture
Harold Edgerton Center
Edgerton Explorit Center
High Speed Visualization Lab...Cool Pictures

Technorati tags: classical education, science, homeschooling, physics, history of science