Broaden Your Physics Background

I was recently asked by someone what would I suggest that might perhaps maybe help broaden one’s understanding of physics. The “might perhaps maybe” was not part of the question. I’m just stuffing that in there to sow the seeds of uncertainty concerning any specific result that may come from following my hair-brained (or is it hare-brained ala Bugs Bunny) ideas.

I apologize now for the meandering twisty path of my answer. I take the question very serious and thus I feel it is necessary to sneak up on the answer.

Some time during the past 50 years memorization has been substituted for learning. I blame George Bush for this — as I do everything from health care to the economy. Perhaps it’s not his fault. It might just be the manifestation of a general trend toward bottom-line thinking that demands quantifiable measure of success. Whatever the cause, memorization and regurgitation of data has become the modus operandi of eduction.

Understanding and wisdom cannot come from a strict diet of memorized facts. These two higher forms of learning come from a foundation of experience.

In Physics 101 we addressed the question of angular momentum. It went something like the following:

Professor: In physics, angular momentum is a vector quantity that represents the product of a body’s rotational inertia and rotational velocity about a particular axis. It can be calculated from the equation: L = r x mv

Student: Say what?

Professor: Think back to when you were a kid swinging a bucket of water on a rope around your head.

Student: (shakes head indicating “yeah, I remember doing that.”

Professor: The force that kept the water from falling out of the bucket was angular momentum.

Student: Ah.

At the time the above conversation occurred swinging a bucket of water around your head was something that was part of the general experience of kids. Not sure why it was so common. Might be a regional thing. Might be a “time of the century” thing. Whatever it was, we shared a common experience of swinging a bucket around out head, observing that the water did not drain out. At least the experience was common enough that the professor was able to rely upon it to help us understand the topic.

If you did a poll of today’s elementary school kids, I doubt you would be able to find more than 1 or 2 kids that have tried such an experiment.

If not having swung a bucket around one’s head was the only experiential deficiency that children had there would be no problem. For whatever reason children have an ever decreasing basis of experiential data. I suppose if one wanted to put a cause to it, the fact that visual and auditory input has become the vast majority of our daily experience could be held accountable. Kinesthetic learning is decreasing as a result.

Now we are getting close to a beginning answer to the question: “How do I broaden my physics understanding?”

To start with, more kinesthetic learning would be most excellent.

However, since this question came from an adult, the answer needs a small modification. It will not be enough to go forth and gather experience personally experienced. A trick will be required. Something  that will encourage you to go back over things which you learned years ago, or think you have learned years ago.

The surest way to do this is to teach another.

To accomplish this, I suggest you create a set of table-top demos designed to teach another about specific aspects of physics. I will illustrate.

Consider the following table top demo.

  • Place a large square of modeling clay on the table.
  • Hold a wooden sphere above the clay (at a known distance — 1 meter would be good).
  • Now open your fingers and allow the sphere to drop into the clay. This will leave an indent in the clay.
  • Measure the depth of the indent left by the wooden ball.
  • Repeat the above steps with a metal ball of the same size.
  • Measure the depth of the indent left by the metal ball.

All things being equal, size of ball, distance from clay, thickness of clay, density of clay, etc… which ball made the larger indent in the clay?

Repeat the above experiment 10 to 20 times. Repeat until somehow the observation goes past the head brain and seeps into the body.

That is a table-top demo.

This will give the experimenter the personal experience personally experienced that heavy objects will make a bigger indent than lighter objects of the same size. Later, when studying a topic such as Newton’s Second Law of Motion F=ma will suddenly mean something.

Remember, the table-top demo does not include equations or theory. The experimenter is free to use that experiential data in any fashion that fits.

How would you change the above demo to incorporate the observation of vector angle on the results? This is not a quiz. I’m asking to demonstrate how extension of each table-top demo will call upon all of your current knowledge/understanding and force you into new area and levels of refinement.

This creation of table-top demos will accomplish two things:

  1. Help you broaden your understanding of physics
  2. Give anyone (child or adult) access to a resource that might help broaden their experiential data.

This is a good thing. Helping others is always better than just focusing on yourself.

This is one method that has the possible result of broadening one’s knowledge/understanding of physics.