THERMODYNAMICS...THE HARD WAY
I come from Chumuckla, Florida (a place that is closer to LeFlore,
Mississippi—in
land miles and in the nature of the land and its people—than it is to Tampa,
Florida).
In Chumuckla we learned about physics early in life. It was not the stuff about
quantum theory and black holes. It was of a more practical nature. My first lesson,
as I remember it, focused on the theory of "Thermodynamics," or the
transfer of heat.
In 1957 my big brother and I were second and third graders at Chumuckla School.
Jim and I commuted by bus. "Number 53" came by our farm every weekday,
grinding gears and belching blue smoke. Some days we waited over half an hour
for "Ol' Man" Claude Jernigan to get to our stop with the bouncing
yellow box on wheels. In the wintertime, the temperature often dropped to a toe-freezing
liver-congealing cold. As native Floridians, we knew we did not have to own a
coat—let alone wear one. It was our privilege.
But the northern state of Alabama refused to cooperate. Frequently, a blast of
frigid Alabama air would slip, unannounced, 15 miles south of the border, where
it would park right on top of our pink exposed ears. It was our preference to
not wear a coat. To do so would be an admission of frailty. Never would we admit
the need for a coat on a freezing day. My brother and I were much too tough.
The lack of a coat, however, spurred creative thought and activity on our part.
In these conditions, as we waited for the warm, if noisy, shelter of the bus,
we discovered what is known as "radiant" heat. The sun, you see, would
pass heat energy to us along with the light energy—if we stood directly
in its glow. The blacktop highway warmed up, stored the heat overnight, and radiated
part of the energy back to the air above it.
At this point you have probably realized our discovery of "Prevost's Law." It
mathematically describes radiant heat: (Q/_) - dA(t4 - tb4). Not long afterward,
we discovered another formula: Q - KA(t2 - t_/d)_. As you know, this formula
explains the theory of convective heat. Heat stored by the black-topped highway
would pass directly to our goose-bump-infested skin merely by forcing direct
contact between the two. So we decided to lie on the highway to absorb heat directly
from the warm tar.
We did this for a couple of very cold mornings. If we saw a car top the hill
or heard a car engine in the distance, we jumped up immediately and rushed off
the road. Then our bare flesh cooled down again, a result of the "Alabama
Arctic Air," and it was back to the road and convection heating.
It was a sensible approach to our problem. Developing motor skills and reflexes
from dodging the cars was a bonus in our physical development—we felt!
Learning about "thermodynamics" was an exciting discipline.
One morning, as she drove to school, my second grade teacher, Mrs. Whitley, saw
Jim and me performing this practical application of physics. She, too, found
the experience exhilarating. Jim and I could tell, because when she hit the brakes
and skidded, her eyes were wide with excitement (and terror). She reported our
brilliant discovery of "thermodynamic principles" to our parents that
same day. After school, Momma explored the "thermodynamics" of applied
friction with us. It was a lesson in practical physics that made a significant
impression on our—minds.
Soon after the incident, Jim and I began to wear jackets. We even wore our jackets
in moderately cool weather.
THE PRACTICAL APPLICATION OF ELECTRICITY
We learned electrical engineering in the 10th grade at Chumuckla School.
Part of our Vocational Agriculture curriculum, it was taught by Mr. Norman "Plug" Walther.
Arc welding was our experimental medium.
The objective, of course, was to learn about electricity. But we were also
to try constructing something of a useful nature that we could apply to the
farming profession. My brother, Jim, constructed a most ingenious thing—a
tractor lift. It was driven by the power lift of the tractor itself. It was
a prodigious invention.
Jim applied the formula for leverage (T = f x l) to produce the contraption.
When placed in commission, it lifted the entire back end of a Ford "red-belly" off
the ground. The arrangement allowed us to swap both rear tractor tires from "inside
configuration" to "outside configuration" with minimal effort.
I never built anything so useful with my arc welding skills.
One day, it was my job to assist another welder. In my bare hands, I held
the metal clamps that joined the steel parts together. The weld was moving
along
at a good pace. It is easy to tell when a welding job is being done properly.
The sound made by the electric arc approximates that of a brown, grade B,
medium hen's egg frying in a cast iron skillet in hot, day-old bacon grease.
I stood on a thick rubber mat for insulation. However, early morning "Dixie
Dew" covered the mat, canceling any insulating effect. I did not notice
the dampness. My body was, in fact, an electrical ground conduction device
for the arc welding machine.
When the shock came, it charged my body with enough electricity to perform
the dance of a thousand battery-operated toy bears running on a parallel
bank of two thousand "D-cell" "Neversaydie" super nickel-cadmium
batteries. The electric jolt cured my acne problem for a week. The pain of
the experience brought tears to my eyes.
One of the Enfinger boys teased me for being a cry-baby. With tears flowing
down my now clear-complexioned cheeks, I let fly with a right hook and hit
him squarely on the jaw. (I do not recommend this response...it hurts the
hand worse than it hurts the target of your misspent emotion.) More tears
followed
as I realized from my bruised hand that I would never become a concert pianist.
And that's how I learned all I will ever need to know about electrical engineering.
THE FLORIDA STATE FAIR
The year was 1964. I was not educated in the world of complex physics. E=mc2,
black holes, and quarks were things I would not hear of for several more
years. But our Vocational Agriculture teacher, Mr. Walther, was a determined
educator. He started me and my fellow Future Farmers of America on the
road to discovery.
"Plug" Walther packed seven juveniles into the school's green International
Harvester pickup truck. The truck carried a drafty aluminum camper shell over
its bed. It took all of us to Tampa, where we were expected to judge livestock
in State competition. Each of us had about $25 to spend. We wore our blue and
gold FFA jackets with the pride of gloried peacocks.
Some of us had never seen a building over ten stories tall. The old San Carlos
Hotel in Pensacola was the tallest building within a hundred miles of Santa
Rosa County. Our hotel in Tampa had nineteen floors.
My brother Jim, Eddie Kilcrease and his cousin Jimmy, and I climbed to the
roof of the hotel, where we threw toilet tissue over the edge of the building,
into the wind. The paper trailed through the twilight, wafting gently to
the streets below. It was a majestic view.
We then tried heavier objects. Somebody dropped a rock. We carefully timed
its descent as it sailed earthward and crashed into the pavement. We imagined
ourselves as young Galileo Galileis researching the law of freely falling
bodies.
Someone found a bolt lying loose on the roof (it wasn't me!). Now, we could
execute a worthy experiment. Which falls faster, a rusty metal bolt or a
roll of toilet tissue?
Oddly, it was not the law of gravity that brought our scientific research
to a halt. It was an obscure and insidious law of physics called "The Coriolis
Force." It states, in so many words, that an object in motion over the
earth's surface will not necessarily fall where a fourteen year old believes
it should, because the object isn't the only thing moving. The earth is turning
underneath it as well. So both the object and the earth are in motion.
It seems the earth turned just enough to place the hotel restaurant skylight
directly underneath the rapidly descending bolt. The sound of exploding glass
signaled an end to our experiment.
I have as yet to explain, however, why the toilet paper fell through the
hole exactly 2.3 seconds behind the bolt. My laboratory notes and mathematical
calculations
made at the time do not explain it. The question haunts me to this day. I
hope to complete the experiment when I am not under the control of a strict
legal
guardian. (My wife thinks the idea is ludicrous.)
The culprit and all his laboratory assistants were quickly rounded up. In
fact, "Plug" collared
the entire livestock judging team, including Kenny Horton, Wayne White, and
Jeff Bohannan. All of us experienced yet another lesson in thermodynamics by
applied friction. "Plug's" genuine tanned cowhide S. S. Kresge
belt left its warm impression.
The hotel staff cordially and singularly invited us to never again break
bread with them or to grace their lobby with our presence.
I don't remember much about the "State Fair" except I saw one of
the largest hogs I had ever seen or expect to see again. Those of us who were
in Tampa that year, however, will tell you that our knowledge of "practical
physics" was given a considerable boost for our having been there.
In the future, "Plug" would use greater discrimination in choosing
the livestock judging teams that represented our school. They would be less
scientifically inclined.
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