Porter
Johnson *67 shows secondary school teachers how to incorporate
interactive, real-world examples in their lesson plans. (Courtesy
Illinois Institute of Technology)
A
whole new ballgame Porter Johnson *67 teaches the physics of baseball
Porter Johnson *67, a baseball fanatic, knows the conditions that
make the air ideal for hitting home runs: high altitude, which reduces
air resistance; warm temperatures, which decrease the air’s
density; and high humidity, which allows the ball to travel through
lighter-than-air water vapor. It’s information that would
be especially useful to power-hitting first basemen, but Johnson,
who earned a Ph.D. in physics and specializes in particle theory,
prefers to relay the knowledge to high school science teachers and
their students.
Johnson teaches the science of baseball in his work as a co-director
of SMILE (Science and Mathematics Initiative for Learning Enhancement),
a Chicago-area program that encourages secondary school teachers
to use interactive examples in their lesson plans. He works primarily
with teachers, some of whom have invited him to visit their classes
as a guest lecturer. “The idea is to enrich the experience
by having students see what science is, not just hear about it,”
says Johnson, who has been a professor of physics at the Illinois
Institute of Technology for 36 years.
The laws of physics are everywhere, according to Johnson, from
the expansion of strings that flattens the tune of violins in warm
weather to the V-shaped position that ski jumpers take in flight
to reduce air resistance. But baseball is always the favorite for
Johnson’s audiences, perhaps because of the professor’s
encyclopedic knowledge of the topic.
Growing up in Chattanooga, Tenn., Johnson came of age in Mickey
Mantle’s prime and faithfully followed the New York Yankees.
He recalls listening to the final innings of Don Larsen’s
perfect game in the 1956 World Series. “The principal played
the game on the public address system to the whole school —
this was considered a historic event,” he says. “Sputnik,
interestingly enough, was not, except by me.”
In the classroom, Johnson’s most popular lesson involves
showing how and why a curveball works — because of the Bernoulli
effect. As a right-handed pitcher spins the ball counterclockwise,
he says, the speed of the air over the surface of the ball on the
left side is greater than the speed on the right side, forcing the
ball to curve left. Johnson also enjoys illustrating the mechanics
of baseball through numbers. For example, a pitcher releases the
ball about 66 feet from home plate, and a 90-mile-per-hour fastball
travels more than 132 feet per second. So batters have less than
half a second to react and make contact with the ball.
Seeing baseball as a set of formulas has not made Johnson a dispassionate
observer. If anything, he says, it gives him a greater appreciation
of the players’ talents. And like most fans, he cannot resist
the chance to critique the umpires — scientifically, of course.
“The umpire misses the call [ball or strike] on 5 to 10 percent
of the pitches,” he says. “He just can’t see well
enough because the catcher is always blocking his view. ... Perhaps
baseball would be well served if they had a telemetry system”
to measure the ball’s position as it crosses the plate.
