Coming to Terms with Science

In Mortimer Adler and Charles Van Doren’s classic treatise “How to Read a Book,” the authors enjoin the reader to be sure to understand the book’s subject fully before undertaking to criticize it. Reading analytically requires a number of stages, they assert, and once the first stage is past – that of knowing what the book is about and what problem it endeavors to solve – the second stage begins with “coming to terms with the author.” In short, this involves identifying the important words used by the author, their “terminology,” and fully understanding the meaning intended by it. For some books, the word may be commonly used in one way on the street, but is given a very specific meaning in the context of the book.

Scientific terminology has exploded. Adler and Van Doren say that good scientific literature, which used to be written for lay and expert readers alike, is now (and “now” was the 1950’s) written for the elite specialists in specialized fields, which have their own lingo, their own terminology. I’ve found coming to terms a much more daunting task with science. Fortunately, there are still books about science written for the curious but unspecialized mind, and these are perfect for introducing your upper grade students to science. This is why I am so enthusiastic about using living literature for high school science, instead of the textbook.

In Charlotte Mason’s educational method, the study of vocabulary outside of its context is not encouraged. Likewise, memorizing long lists of nomenclature – of animal families, or chemical names and the like – would also be discouraged in a Charlotte Mason education. However, most of us, with our kids’ history readings, will jot down two, maybe three words that may confuse our student and define them so they can read the passage fluently. And, we will make sure that our child sees and knows the names of the main characters. A single science reading may be all about understanding the meaning of a given term, just like a history reading may be all about understanding the ideas and work of a given person. A single term represents an idea, a concept, or even something real. Miss T., reading about Metchnikoff yesterday in Microbe Hunters, was also introduced to the phage. Two important characters in the study of immunity to disease.

I’ve found it helpful to think of scientific terms as characters, particularly as Miss T. is reading about electricity in her physics book. She has needed to understand the intricate family relationships between the coulomb, the volt, the joule (whom she’s met before), the amp and the watt. Like Churchill does in his English history series, Asimov often uses different names for the same character – sometimes without much warning. So the volt and “electric potential difference” are the same thing. So are the amp and “current intensity.”

Our science notebook, then, works in much the same way as the spiral bound notebook in which I encourage my daughter to jot down the names of her historical characters. She needs to keep track of all these new ideas, and their names and relationships as well. Pictures work especially well, mathematical relationships with labels are also good, but at the very least a few notes should show up. One of my favorite (though difficult!) chemistry works is P.W. Atkins’ Periodic Kingdoms, which likens the periodic table to a map, with different areas of similar elements representing countries. Diagramming relationships in this way in your science notebook can also be fruitful.

Further, because the “characters” in a science text are still very much alive, I will try to introduce her to them personally. I will prick my finger and introduce her to a living phage. We will play with an electric circuit and meet volts, and amps, and watts, and see how they play together. In this way, science is truly “living” science.

Understanding Physics

Miss T. understands physics, far better than I ever could. So while our less than traditional method of learning it at home – without a text or math problems – may not help her pass an SAT, I know that once she takes one of those courses she will be in a better place to put the math in context than I ever was.

This week we started in on the wonderful world of electricity in her book, Asimov’s Understanding Physics. First, we worked on understanding magnetism. Now we’re on to what is known as static electricity, the first form of electricity studied in the 17th and 18th centuries. Electricity and magnetism, as any quantum physicist knows, are pretty much two forms of the same phenomenon. I thought I had a pretty good grasp of this, but, as it turns out, my grasp was limited. And I worried that Miss T’s was as well, because she refused to take what she learned and diagram it into her notebook.

Miss T. just hates to draw, but she does love painting word pictures and she also loves the science blog “what if?” on xkcd. While the section she read for the day was only 4 pages long (science readings being far shorter than a comparable reading in literature or history), we still broke it into pieces for her narration. She reviewed the discovery of subatomic particles, the understanding that the electric “fluid” of Ben Franklin’s day is actually flowing electrons, and the reversal of the concept of “positive” and “negative” charge. (Miss T’s dad, who studied electrical engineering in college, confirmed that electrical engineers still maintain the idea that the direction of flow is from positive to negative, and use the concept of “hole current” to describe this flow). The next concept she narrated concerned how electric force is measured, and while she understood the idea that gravitation is a far weaker force controlling electrons than electric force, she skipped over how Asimov demonstrated this mathematically. Finally, we arrived at the concept of electric lines of force.

Here’s where my understanding fell apart. Because electricity and magnetism are basically two forms of the same phenomenon, as any quantum physicist knows, there are analogous terms for similar observations. However, the ideas started to challenge what I thought I knew about electricity.

The permittivity of substances is just such a challenge. Permittivity refers to the attraction a substance has for electric lines of force. A substance is an insulator if it allows the lines of force to pass through it, and the ratio (or relative permittivity) of the density of lines of force through the substance vs. through a vacuum is called the dielectric constant. Air has a permittivity of close to 1, the value of water is 78. Water is considered an insulator or a dielectric.

“Whoa there!” I said. “I thought an insulator stopped electricity! It couldn’t possibly attract lines of electrical force.” And, in fact, Asimov had said so in the preceding section, when discussing Stephen Gray in 1729 discovering that certain substances resist the flow of electric fluid. They are called insulators from the Latin word for “island” because they “wall off electrified objects, preventing the fluid from leaving and therefore making the objects an island of electricity, so to speak.” (Asimov, Understanding Physics, p. II-159)

Miss T. was silent, so I read aloud the concluding paragraph:

Electric forces between charged particles decrease, then, if a dielectric is placed between; they decrease more as the dielectric constant is increased. The constituent particles of a substance like common table salt, for instance, are held together by electric attractions. In water, with its unusually high dielectric constant, these forces are correspondingly decreased, and this is one reason why salt dissolves readily in water (its particles fall apart, so to speak) and why water is, in general, such a good solvent. (p. II-165)

“The only way that makes sense to me,” I said, “is if you can separate the idea of electric force from the flow of electrons.”

Miss T. was silent, her eyes closed. I thought she was shutting me out, but she only said, “Wait a minute, Mom, I’m going to help you with an analogy.”

Dialectric.001

Finally, she came up with this word picture, illustrated above in the xkcd style. “Imagine you are an electron, and you are running. Think of your kinetic energy. Now think of a brick wall.”

“The brick wall takes all of your force, your kinetic energy, and disperses it through the bricks. Air will not absorb your kinetic energy, so the force stays with you and allows you to pass through. That’s what happens to the electrons.”

So I, who spent most of her life thinking that “ekeltricity” (the word of a semi-famous wizard) was just some form of wizardry, may just get a handle on this, thanks to my daughter’s power of analogy-making. This further demonstrates to me the power of narration, even at the high school level, even with a subject I couldn’t possibly understand well enough to teach. For if my daughter can understand it well enough to make me understand it, she’s learned her stuff. In science, particularly upper level science, it doesn’t do to let a less than complete narration pass. Find a way, any way, to help the student access the idea.