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Physicsygoodness.com, a collection of resources and tools for students of physics, is the ongoing project of Hal Wright, a physics teacher and website designer living and working in southeastern Pennsylvania.
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Article | July 13, 2019
Why Physics?
Article | July 13, 2019
Why Physics?
Why Physics?
A message to students enrolled in my classes
The goal of this class is that you learn some physics, enough to impress me and enough to impress the colleges to which you are applying. In furtherance of that goal I will be working very hard for the next nine months, and I expect you will be too.
Throughout the school year, I will be describing many examples of events in the natural world. Some of these events will be very familiar to you. For example, I may describe the act of hitting or kicking or throwing a ball, or the act of playing a musical instrument. And we will discuss and analyze the particulars of these events as physicists see them.
Now, you may spend significant time actually hitting or kicking or throwing the balls we will talk about, or playing the musical instruments we will talk about. Or you may dance or lead cheers or do gymnastics -- what I am going to say applies to pretty much any activity you care deeply about and pursue passionately. You may reach the logical but inaccurate conclusion that I believe the key to understanding these activities is “all in the physics.” You may be tempted, therefore, to view the proceedings and the instructor with skepticism: You know it’s not all in the physics. You know that the essence of things like sport and music does not live in science. You know this intuitively, but it can be explained.
In baseball, players in the middle of a hitting streak say the ball looks “as big as a melon” (or words to that effect). Musicians don’t generally think about physics when they’re playing their instruments. They often can’t even say where the music comes from…it just comes. A popular expression for this feeling not too long ago was “being in the zone.” In the zone, there seems to be no separation between you and the bat and the ball or you and the instrument and the music itself. There is a wonderful convergence of matter and energy and consciousness; an inspiring moment to be alive. Some would say a spiritual moment, although others would say that’s overdoing it a bit.
In any case, science can’t own that moment, because science depends on rational thought, and rational thought requires dispassionate observation. Science requires an observer, the scientist, you. You have to try to be impartial, separate from the action. You can’t be in the zone, and so the essence of the moment is lost.
It seems as though I’ve given you a reason not to study physics, but that’s because you haven’t read the whole essay yet. The physicist in you may be on vacation when you’re in the zone, but the physicist in you and many other physicists as well are involved in creating the environment needed to get there. If you’ve been coached on how to swing a baseball bat, your coach (consciously or unconsciously) was drawing on the physics of a proper swing. And there are good reasons, grounded in physics, why musical instruments look the way they do. Behind the scenes, physics improves just about every activity you can think of.
Knowledge of physics enhances and complements other knowledge you have acquired and will acquire. It is necessary to your being an enlightened person in this modern world -- necessary, but as we have seen, not sufficient.
Studying physics will improve your rational mind, your ability to make decisions based on logic, and your mathematical ability. Studying physics will help you think about your own thinking: It will help you to know when you’re being rational, and when you are making decisions based on faith or impulse.
In a broader sense, physics does not detract from but rather contributes to our sense of wonder as we contemplate the natural world. The theoretical framework constructed by physicists to describe the universe -- objects billions of light-years away, the big bang, black holes, elementary particles small enough to be the building blocks of protons -- is nothing if not wondrous. And that there should be living things such as we with the ability to construct elaborate models to describe the universe -- that’s pretty amazing too.
In short, physics is good for you, and it will be my pleasure to teach it to you.
A message to students enrolled in my classes
Article | July 13, 2019
Those who do not successfully resolve the issues of one stage of life bring "excess baggage" into the next stage. This inhibits their ability to mature into independent, productive and happy citizens.
Cognitive and Developmental Models
Article | July 13, 2019
Cognitive and Developmental Models
Cognitive and Developmental Models
In my teaching, I keep numerous models of child development and education in mind.
In my teaching, I keep numerous models of child development and education in mind. Here, they are described for your reference.
"Some people polish on cars, I polish on kids."
--Ernestine Rouse
Contents
Early Models
Religion provided the earliest justification for mass education. For example, the Christian ethic holds that the child is "born in sin." Morality must be instilled in the child.
Rationalism , a philosophy espoused by (among others) Spinoza, DesCartes, Rousseau and Thomas Paine, held that the child's mind is a tabula rasa -- a blank slate -- at birth. Through exploration and experimentation, the child uses his senses and cognitive powers to form accurate models of the natural world.
According to Romanticism , a movement that affected the literature, art and music of the 1800s, children are born free and naturally good, but can be corrupted by society.
B. F. Skinner (1904-1990)
Skinner, the chief proponent of behaviorism, believed that children respond to sensory input in predictable ways. According to behaviorism, there are two ways to encourage a given behavior, that is, to increase the likelyhood that it will be repeated. The first, called positive reinforcement, is a "reward" received immediately following the behavior. The second, called negative reinforcement, is a reduction in physical or psychological pain accompanying the behavior.
Punishment, an undesirable stimulus, tends to suppress the behavior that immediately proceeds it.
Note that positive reinforcement, negative reinforcement and punishment may be caused by a behavior, or merely coincident with it. Many of the discipline strategies used in schools, from the candy jar on the teacher's desk to detention, are "artificial" stimuli imposed on students by the adults in charge, intended to encourage or suppress specific behaviors. Rapid imposition of the reward or punishment, and linkage to the related behavior, are essential to success. For example, a student who writes on a desk may be unlikely to repeat this behavior if she is made to clean the desk on the day of the writing. If a detention is assigned and served one week after the infraction took place, there is only a remote connection between the behavior (writing on the desk) and the stimulus (the detention). This is usually an inferior method of discipline.
Skinner's approach tends to imply that children are somewhat savage by nature and need to be tamed. Anyone who has witnessed an unattended class of 30 sixth graders might be tempted to agree with this assessment. But as we shall see, reality can be a little more complex than Skinner's philosophy would predict.
Abraham Maslow (1908-1970)
"Man is a wanting animal."
Maslow believed that a human life is spent satisfying needs, such as the need to survive, the need to belong, and the need to create.
Maslow's classified all human needs based on the following hierarchy:
Basic needs -- food, water, oxygen
Safety needs -- security and shelter from the environment
Love needs -- belongingness, affection
Esteem needs -- self respect, stability, confidence
Self actualization needs -- accomplishment, productivity, creativity
Safety needs -- security and shelter from the environment
Love needs -- belongingness, affection
Esteem needs -- self respect, stability, confidence
Self actualization needs -- accomplishment, productivity, creativity
Pedagogically, the most important element of Maslow's philosophy is that an individual sets about satisfying these needs in the order presented in the hierarchy. Thus, a hungry person -- someone whose basic needs have not been met -- is relatively unconcerned about security (a safety need) and cannot focus significant internal resources on seeking and giving affection (a love need).
More to the point, Maslow would say that the intrinsic motivation to learn lies in satisfying esteem and self actualization needs. If a child is hungry, or lives in a dangerous neighborhood, or is neglected in the home, esteem and self actualization needs generally are not activated. The desire to learn is diminished or extinguished.
Interesting things happen where Skinner and Maslow intersect.
Jimmy, a neglected child, may act out to garner attention from his teacher. The teacher gets angry, but Jimmy perceives (accurately) that this anger is an expression of concern. The teacher's anger, therefore, is a positive reinforcement. Jimmy repeats the behavior, the teacher gets angrier, and...you get the idea.
Erik Erikson (1902-1994)
Erikson believed that human development hinges on the individual's response to a series of challenges that inevitably present themselves throughout childhood and early adulthood. At each stage of life, the individual grapples with a different issue.
| Age | Issue | Potential Positive Outcomes |
| 0-1 yr | trust vs. mistrust | inner drive, hope |
| 1-3 yrs | autonomy vs. doubt | self control, will power |
| 3-6 yrs | initiative vs. guilt | direction, purpose |
| 6-12 yrs | industry vs. inferiority | method, competence |
| 12-19 yrs | identity vs. confusion | devotion, fidelity |
| 19-25 yrs | intimacy vs. isolation | affiliation, love |
| 25-50 yrs | generativity vs. stagnation | productivity |
| 50+ yrs | integrity vs. despair | wisdom |
Those who do not successfully resolve the issues of one stage of life bring "excess baggage" into the next stage. This inhibits their ability to mature into independent, productive and happy citizens.
Astute educators look at students holistically, within the context of Erikson's model.
Mrs. Alcott, a high school English teacher assigns reading in which characters are struggling to establish an identity, and design assignments to help the youngsters explore their own identities. This is one way to teach the child, rather than simply teaching the curriculum.
Jean Piaget (1896-1980)
Piaget studied the development of the human brain's ability to reason and, more generally, to process sensory information. He discovered that the brain goes through stages of growth according to the general scheme described below.
1. Sensorimotor Stage (age 0-2 yrs)
In this stage the child learns
- to differentiate himself from his environment,
- to use motor skills and the five senses to discover the basic properties of objects,
- to use memory and historical patterns to make rudimentary predictions,
- to integrate motor skills with intent,
- to associate sounds (words) with objects and simple actions.
Note that the emphasis is on interaction between the child and his or her environment.
At age 3 months, Gertrude's mother plays a game in which she shows a stuffed rabbit to Gertrude, then hides it from view. Gertrude makes no effort to find the rabbit when it is out of view, but seems delighted every time it reappears. At age fourteen months, Gertrude notices that Mom has placed the missing rabbit behind her back and scoots around Mom to look for it. When Mom puts the rabbit in a different location, Gertrude still looks behind Mom's back.
At age six months, Getrude is able to reach out, grab the rabbit, and seems to notice and enjoy its softness. By age two years, Gertrude can remember that Mom puts the rabbit in the toy bin when she tidies up, and she can retrieve it from the bin at will. She associates the word "rabbit" with the stuffed animal and says the word sufficiently well for Mom to understand it.
2. Pre-Operational Thought (age 2-7 yrs)
During this stage of learning, the child first grapples with more advanced mental concepts but often falls short of total understanding. It's the struggle that's important.
Typically, the child will focus on the most obvious single characteristic of an object or situation, and draw illogical conclusions and inferences. The most well-known of these is young children's inability to conserve quantity and volume. For example, when they see a fixed volume of water being poured from a tall, thin container to a short, wide container, the children will interpret that the water's volume has been reduced because the level of the water is lower.
Young children are also egocentric. They assume that everyone is seeing, thinking and feeling whatever they see, think and feel.
Jasmine decides that movement is proof that an object is alive, and so concludes that a car is alive. She is confused by others who hold a different point of view. Her adherence to her own point of view is unshakable in spite of exposure to alternative explanations.
Egocentrism also involves the feeling that all events are caused by the child, or for the benefit of the child.
Albert believes that his frequent nightmares are punishment for bad behavior.
Much thought at this stage centers on symbols of actual events, such as drawing, language, imitation and play.
Susie, age 4, might take comfort and pleasure in imitating the back and forth motion of her mother cutting the grass with a lawn mower. Although she is not being productive in the sense that work is being done, Susie is emulating an obvious feature of her mother's activity and therefore beginning the process of understanding it in greater detail.
Children begin to master the formal rules of grammar at this stage.
3. Concrete Operations (age 7-11 yrs)
At around age 7, children begin to be able to truly master mental (logical) operations. Perhaps the most obvious manifestation of this transition is the ability to learn addition, subtraction, multiplication and division. At the beginning of this period, children start to notice and process multiple characteristics of objects. They begin to conserve. They can conceive of seemingly continuous objects such as clay or liquids as being made of smaller pieces whose individual positions can vary. They can explore cause and effect relationships in a meaningful way.
There is a marked decrease in egocentrism. Children can take another's point of view into account. Also, children can appreciate some of the subtleties of language, for example, metaphors or riddles involving the multiple meanings of words.
Children in the concrete operations stage can do all of this only where everyday objects or people are concerned. Abstractions (such as representing numbers with letters in algebra) are difficult or impossible for the children to handle.
4. Formal Operations (age 11 to adult)
Around age 11, it becomes possible for children to master formal operations that do not necessarily involve thinking about everyday objects and people. Thus they can master concepts relating other concepts. For example:
- The meaning of the word government expands to include any body of people making decisions for an organization, not just actual governing bodies the student has studied.
- The student can learn the concept of a ratio, a fractional comparison of two different quantities, rather than just studying examples of ratios.
- The child can think about his or her own thinking, and monitor understanding, a skill called metacognition.
Not every person masters this stage of learning. The child's degree of comfort with formal operations is a major discriminator with respect to his or her success in secondary school and college.
Moving Between And Within Stages
Piaget theorized that learning happens because humans have an innate need to process sensory experiences either by assimilation (explaining the event in terms of prior knowledge) or accommodation (constructing new knowledge structures to account for the new information). Piaget believed that movement between the stages is linear and abrupt, although different children progress at different rates.
Benjamin Bloom
Bloom's Taxonomy (1965) is a way to classify questions based on the nature of the thought required to answer them. There are six levels of questions, two that require "lower order" thinking and four that require "higher order" thinking.
Lower Order Thinking
1. Knowledge
Knowledge questions test familiarity with basic facts. Answers are given "verbatim." Examples:
- Give the capital of Pennsylvania
- What is the definition of pertinent ?
- When did the Civil War start?
Knowledge questions do not test understanding.
2. Comprehension
To answer comprehension questions, students must rephrase basic information in their own words. Examples:
- What was the main idea of the second paragraph?
- What did you see on our trip to the museum?
- Compare bacteria and viruses.
Higher Order Thinking
3. Application
Application questions require students to use general techniques and strategies to solve specific questions. Most mathematics problems are application questions. Examples:
- Solve 3x + 7 = 34
- Are lice insects or arachnids?
- Give an example of a metaphor.
4. Analysis
To answer analysis questions, students must draw a conclusion supported by relevant information from source material in which the answer is not explicitly stated. The question "What is the purpose of the turbocharger on this engine?" would be an analysis question if the purpose had not been previously provided to the student, but if he or she had been instructed on the principles of internal combustion engines.
5. Synthesis
Synthesis questions demand thought that is both original and creative, and the production of output that is unique to the student. Examples:
- Write a poem about growing up.
- Design a model bridge using only glue and toothpicks.
6. Evaluation
Evaluation questions give the student the opportunity to make judgements about the value of intellectual work or physical materials. When you are asked to say which artist you prefer, to give your opinion, or to say whether you agree with an expert's assessment, you are being asked an evaluation question. To provide a complete answer to an evaluation question, one must articulate a set of criteria upon which the judgement is based. These might be objective criteria or unscientific personal beliefs.
Sources
These summaries were compiled based on notes from Ernestine Rouse's class at Drexel University, and with help from the following texts:
- Reisman and Payne, "Elementary Education, A Basic Text" (Columbus: Merrill Publishing Co., 1987)
- "Classroom Teaching Skills," ed. James M. Cooper (Lexington: D.C. Heath and Company, 1990)
- Schell et. al., "Developmental Psychology Today" (New York: Random House, 1975)
In my teaching, I keep numerous models of child development and education in mind.
Article | July 13, 2019
Science and Reading: A Key Connection
Article | July 13, 2019
Science and Reading: A Key Connection
Science and Reading: A Key Connection
Some of the reading strategies commonly used by proficient readers are ineffective when applied to scientific writing.
Students who have always excelled in school sometimes "hit a wall" in high school science. For these students, high school science represents the first genuine academic challenge. In many cases, the source of the difficulty lies in the differences between scientific writing and everyday language.
Experts say that many proficient readers skip over words they don't understand, but accurately garner the overall meaning of text using cues in surrounding words and phrases. By contrast, less proficient readers tend to become fixated on every unfamiliar word, losing track of the overall meaning of the passage they are reading.
Experts say that many proficient readers skip over words they don't understand, but accurately garner the overall meaning of text using cues in surrounding words and phrases. By contrast, less proficient readers tend to become fixated on every unfamiliar word, losing track of the overall meaning of the passage they are reading.
Because scientific writing tends to be more concise than everyday language, students are much more apt to misinterpret the meaning of entire paragraphs if they skip over unfamiliar words. Furthermore, even students with excellent word decoding skills can have problems with scientific words that contain unusual root syllables. It is easy to decode houseboat , but decoding transpiration is quite another matter. The only sure fire method of coping with unfamiliar science words is to look them up or to ask a knowledgeable adult.
Fast readers may have to slow down as they read scientific writing. They should frequently ask themselves, "Did I understand what I just read?" If the answer is no, they should reread the passage, identify unfamiliar words or confusing phrases, and seek help before moving on. Students should be able to say, "I don't understand the meaning of this sentence," not just "I don't get it." Thinking about one's own thinking, what educators call metacognition , is the key. The need for metacognition when reading scientific writing is so great that often only 2 - 4 pages of reading are assigned per night.
Fast readers may have to slow down as they read scientific writing. They should frequently ask themselves, "Did I understand what I just read?" If the answer is no, they should reread the passage, identify unfamiliar words or confusing phrases, and seek help before moving on. Students should be able to say, "I don't understand the meaning of this sentence," not just "I don't get it." Thinking about one's own thinking, what educators call metacognition , is the key. The need for metacognition when reading scientific writing is so great that often only 2 - 4 pages of reading are assigned per night.
Be aware that students with well-developed verbal skills can sound scientific without having grasped the concept being taught. In verbal or written responses, one telltale of a lack of deep understanding is the repeated use of phrases that are identical to those in the text. Students should be able to elaborate on the meaning of a passage, or to give other examples that demonstrate the concept being discussed.
Some of the reading strategies commonly used by proficient readers are ineffective when applied to scientific writing.