|
|
Multidisciplinary
Design, Analysis, and
Optimization Branch
|
|
|
| |
EDUCATIONAL ACTIVITIES: THE BASEBALL SERIES FROM THE NASA AEROQUIZ
|
|
|
| |
|
| |
Week of 4/19/99:
Q:
The year is 2030. The Martians, having monitored Earth's radio
transmissions for well over a century, have adopted baseball as their favorite
pastime. The Mars Stars have challenged your team to a winner-take-all
game of interplanetary domination on a neutral venue: the desolate surface of
the moon. Your two ace pitchers, Roger Clemens Jr. - with his blistering
fastball, and Tom Glavine Jr. - with his unhittable breaking ball - have
comparable statistics. Who should start?
A:
Start the fastball pitcher because the breaking ball will not curve
without air.
Congratulations to Ronnie Gladden.
Go with the heat. But just to show that conventional wisdom isn't always
accurate, the only no-hitter to date in the thin air at Denver's Coors
Field was the "Nomo No-No" on September 17, 1996, by LA's curve ball thrower Hideo Nomo.
- The Aeroquiz Editor
Week of 10/25/99:
Q:
"My data indicate a duration of 5.2," said the NASA rocket
scientist.
"I dispute your contention," replied the NASA trajectory
analyst. "The time interval was only 5.1. That asset was jettisoned
after its malfunction allowed an elongated post-percussion
trajectory. The backup systems then were engaged for periods
of 2.0 and 1.2."
The rocket scientist thought for a moment
and said, "Yes, you are indeed correct. 5.1 plus 2.0 plus
1.2 is nine."
Hints abound in this week's question!
Is their addition correct? Or can't NASA get good help these days?
A:
The starting pitcher was in for 5 & 1/3 innings before giving
up a home run. Two relief pitchers were brought in for 2 and
1 & 2/3 innings, respectively. 5 & 1/3 + 2 + 1 & 2/3 = 9.
Congratulations to Dale Martin.
Dale always uses baseball notation math during the World Series!
- The Aeroquiz Editor
Week of 7/5/99:
Q:
In 1852, Henrick G. Magnus made an extraordinary contribution to
baseball. Magnus was not a professional ball player, coach, team owner,
or even a sports writer. What did he do?
A:
German physicist Magnus reported that when a spinning
object (such as a baseball) moves through a fluid (air) it experiences a
sideways force. In the game of baseball, this force makes the spinning ball
curve when thrown by a skilled pitcher. This phenomenon is known as the
Magnus effect.
Congratulations to Stephen Jackson.
Specifically, the Magnus force pushes the ball at right angles to the direction
of flight and to the axis of spin. The Magnus force is responsible for the
curve of the curve ball and the "hop" of the fast ball. This force is a
result of an in-flight drag reduction on one side of the ball. When a
pitcher throws the ball with spin (on the order of 1600 revolutions per
minute for some pitches), the wake of the ball on the side that spins with the flow is largely
eliminated. The lower effective flow velocity on that side mimics low-speed,
attached flow and results in a large drop in the "form drag" on one side
of the ball (See the October '98 quiz
question on the aerodynamics of golf balls for an explanation of drag on
bluff bodies.). For you non-believers (and there were many back in the 1800s
who claimed baseballs could not curve), breaking ball hurler Freddy Goldsmith
threw a ball between three aligned vertical poles in New Haven in 1870.
Also, it is actually Lord Rayleigh who is credited with the first description
of the effect. Henrick Magnus reported it in his 1852 paper "On the
Derivation of Projectiles; and on a Remarkable Phenomenon of
Rotating Bodies." (G. Magnus, Memoirs of the Royal Academy, Berlin.)
- The Aeroquiz Editor
Week of 7/12/99:
Q:
Slugger Jim Thome of the Cleveland Indians is 225 pounds of hard hitting,
corn fed, Peoria brawn. His workout regimen likely includes a hefty
dose of weight training. Would you scoff at a claim that he could
exert over 8000 pounds of force? Why?
A:
The force applied to the baseball in a typical Thome home run swing
is about 8000 pounds, albeit for only one thousanth of a second!
Forces (impulses, more precisely) of these magnitudes are needed to
reverse the direction of a 90 mile-per-hour fastball towards the Jacobs
Field bleachers at about 110 miles per hour.
No one got the correct answer!
- The Aeroquiz Editor
Week of 7/19/99:
Q:
Section 1.10(c) of the Official Baseball Rules reads: "The bat handle,
for not more than 18 inches from the end, may be covered or treated with
any material or substance to improve the grip." Many of us remember the
famous "Pine Tar Incident" of 1983 involving George Brett of Kansas City and
manager Billy Martin of New York. With New York leading 4-3 in the ninth
at Yankee Stadium, Brett homered with two out and a man on to put the
Royals in front, 5-4. Billy Martin contended that Brett should be declared
out and the runs shouldn't count, because his bat had pine tar more than
18 inches from the knob. The umpires agreed, awarding the win to the
Yankees. The Royals protested, however, and league president Lee MacPhail
ended the Pine Tar Incident by overruling his own umpires and declaring
a resumption of play at a later date. Physically speaking, why are
baseball rulemakers worried about pine tar high on the bat?
A:
A ball hit with backspin can provide its own lift due to the Magnus
Effect (See 7/5/99's quiz for an explanation of this effect) and can travel
farther than a ball without spin. Some think that pine tar could enhance the
contact friction during a hit and create more backspin. Pine tar can also
hide "grooving" marks on the bat. A normal ball-bat collision, however,
ordinarily has enough friction to prevent the ball from "skidding" on
the bat while being hit. Batters who illegally coat or groove their bats
are not likely helping themselves.
What scandal would be complete without Billy Martin? Brett came
storming out of the dugout and had to be restrained by several other
men. Even though the game was supposedly over, the umpires tossed Brett,
manager Dick Howser, coach Rocky Colavito, and pitcher Gaylord Perry,
who tried to hide the bat, out of the game. Umpires were able to
confiscate the bat only because, as it was getting passed from Royals
player to player, the last man in the line didn't have anybody to
give it to.
Brett was the only player to win batting titles in three different
decades, a thirteen-time All-Star, and the last recent player to make a
serious run at hitting .400. He was inducted into the Baseball Hall of Fame
this week.
No one got the correct answer!
- The Aeroquiz Editor
Week of 7/26/99:
Q:
The range of speeds at which major league baseballs are thrown and
batted varies approximately from 50 to 130 miles per hour. Below
50 mph, the flow around the ball is entirely laminar; while above
about 150 mph, the flow can be considered to be completely turbulent.
The range of interesting baseball speeds occurs almost entirely within a
laminar-turbulent "transition zone." Why does this help make baseball
such a lively, unpredictable, and entertaining game?
A:
Aerodynamic drag plays an important part in baseball trajectories.
The drag can change dramatically on a baseball flying in the
laminar-turbulent transition zone. Indeed, significant differences
in drag are often present on opposite sides of the ball at the same
time. Knuckleball hurlers, in particular, take advantage of the
variability of the drag transition zone when throwing their slowly-rotating
balls toward the plate.
No one got the correct answer!
- The Aeroquiz Editor
Week of 8/9/99:
Q:
Decades ago, home teams were allowed to dole baseballs out to
the home plate umpire one-by-one. At the time, this practice was not thought
to give an unfair advantage to the home team because the umpire could
easily inspect the ball's surface to see if it had been illegally scuffed
or if an illegal lubricant had been applied to it. Rules now, however,
make this practice illegal. All of the game balls to be used by both
teams must be submitted at the same time a few hours before game time. Why?
A:
The balls are sumbitted a few hours before game time to make sure
none of the balls have been frozen to deaden their response
to being hit.
Congratulations to Philip Stehno.
There are stories in baseball, going all the way back to the days
when John McGraw managed the New York Giants, of putting baseballs into
freezers. Deep freezing a baseball to minus ten degrees Fahrenheit
can reduce the ball's so-called "coefficient of restitution" (a measure
of how well the batted ball rebounds off the bat) by about ten percent.
If taken out of the freezer an hour or two before game time, the outer
surface of the ball becomes warm enough to fool an umpire, but the ball's
center is still very cold. The visiting team, naturally, would bat the
cold, "dead" balls, while the home team would enjoy batting livelier,
room temperature (or even heated) balls.
- The Aeroquiz Editor
Week of 8/16/99:
Q:
One of the longest home runs (and perhaps the longest ever) was
Mickey Mantle's 1953 "Washington Wallop" off of Chuck Stobbs that
went over the left field bleachers of old Griffith Stadium. Although
(naturally) disputed, the distance was estimated at 565 feet by a Yankees
publicity man. What might be the effect on blasts like Mantle's if baseball
is further internationalized to include a team in Mexico City?
A:
The high elevation above sea level of Mexico City (7800 ft) would allow
longer baseball flight distances due to the reduced air density at
that elevation.
Congratulations to Stephen Jackson.
Denver is high enough! If Mantle had hit Stobbs' pitch in Mexico
City, it would have traveled about 40 feet farther due to the reduced
air resistance at the elevation of 7800 feet. A Mexico City team would have
a tremendous impact on pitching. To prevent all home run records from
falling, the team might try moving their fences back. But that would leave
large gaps in the outfield into which hits would fall. Breaking ball
pitchers, with much less air to "bite" into, in particular would suffer.
- The Aeroquiz Editor
Week of 8/23/99:
Q:
Pitchers who throw blistering fast balls are generally young.
Fast ball hurlers often have to develop other pitches as they age
in order to keep in the game (Nolan Ryan, baseball's all-time strikeout
leader, who continued to throw major league heat until age 46, defies explanation!).
But it isn't diminishing strength that slows them down. Indeed, 35-year-old
pitchers are likely a bit stronger than they were at 25. Why do their
fast balls lose speed?
A:
In general, the elasticity of tendons and other tissues decreases with
age or with injury. This reduces older pitchers' ability to throw the
fast ball.
No one got the correct answer!
- The Aeroquiz Editor
Week of 9/6/99:
Q:
Our degree of understanding of fluid and flight mechanics problems
is often a function of how aggressively the physics of these problems
are studied. Perhaps surprisingly, much better and more rigorous
analyses have been made of golfball mechanics than of baseball. Why?
A:
Manufacturers have much greater freedom in designing better golfing
equipment, which often leads to better balls and clubs. Baseball
equipment, on the other hand, is subject to much stricter specifications
as determined by major league officials. This leads to fewer improvements
in the science of baseball.
No one got the correct answer!
- The Aeroquiz Editor
|
|
|
|
