The following article appeared in February, 2004 issue of The Scientific American. The text is mirrored from
It Is High, It Is Far
By Steve Mirsky
But it's not gone, because there are some laws you just can't break
As has been said often in these pages, there's a clear and present
need for better math and science education in this nation. One
obvious place for improvement in our math and science skills can be
found among the hosts of and callers to the country's many sports
talk radio programs.
Image: Frank Veronsky
Recently I was listening to a show on which the host contended that
the Boston Red Sox's payroll had swelled to the point where Sox
fans couldn't complain that the New York Yankees' even larger
payroll gave the Yankees any advantage. A Boston caller disagreed,
saying, "The Red Sox payroll is only $\$120$ million, and the Yankees
is $\$180$ million. You know what percentage $\$120$ million is of $\$180$
million? Seventy-five percent." The host did not dissuade the
caller. This display came from two grown men who spend an
inordinate amount of their time calculating batting averages.
That exchange was about simple arithmetic. But the next morning I
was treated to a lively discussion of Newtonian physics. The two
morning hosts had left the subject of sports for a moment to
discuss national news headlines. One story involved a Ku Klux Klan
initiation ceremony at which a Klansman had fired a gun into the
air. By the way, part of the radio hosts' conversation went
something like this:
"The Klu Klux Klan."
"It's not Klu. It's Ku. It's not Klu Klux Klan,
it's Ku Klux Klan."
"I didn't say Klu Klux Klan, I said Klu Klux Klan."
"You said it again, you said Klu."
"I did not say Klu Klux Klan, I said Klu Klux Klan."
"You said it again. You said Klu."
I was grateful I didn't have a gun. Fortunately, they
eventually departed from the science of linguistics and returned to
classical mechanics. As noted, some Klan member was firing a gun
straight up in the air. You've probably guessed by now that a
bullet came back down, which they tend to do. Well, all the bullets
came back down. But one in particular found its way to the ground
only after going clean through the top and then out the bottom of
the skull of one of the celebrants, critically injuring him. (A
British newspaper headlined this story "Ku Klux Klan Man Shot as
Initiation Goes Wrong." Which raises the question: What Klan
initiation has ever gone right?)
Anyway, the talk show hosts were incredulous that a bullet could
have come down hard enough to do that kind of head damage "just
from gravity," as one put it.
Image: Matt Collins
Now, I wouldn't necessarily expect Klansmen to go in for the kind
of book learning that would reveal that a bullet returning to earth
after being shot straight up could return fast enough to cause
serious injury. What did surprise me was that two men who basically
watch the trajectory of projectiles for a living--batted baseballs,
for example--would be incredulous at the speed at which some
objects return to earth. Hadn't they ever noticed that when a
catcher fields a major league pop-up, where the baseball has gone
almost straight up and down, the ball smashes into that catcher's
mitt pretty darn hard?
In summary, as a public service for guys waving guns or news copy:
stuff that goes up fast comes down fast. In a vacuum, where air
resistance is not a factor, an object sent on a flight has a final
downward speed that is, amazingly enough, equal to its initial
upward speed. I've seen the equations--it's true! Closer to home,
air resistance does indeed slow down a bullet or baseball, but both
still gallop back to earth at quite a clip. And a bullet is pointy.
Clearly, the gunman, who has been charged with aggravated assault
and reckless endangerment, did not intend to hit his victim. Why,
he shot in the completely opposite direction! But ignorance of the
laws of motion is no excuse. Nevertheless, the bet here is that the
shooter gets off and that Isaac Newton gets charged with being an
accessory after the fact. Or, actually, three centuries before.