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AIRPLANES AND GOLF BALLS
Answer to our previous question: Last time we asked you why, if the dimples
on golf balls make them more aerodynamic, there aren't dimples on airplanes.
This question came in from several readers after our discussion of golf ball
dimples a few weeks back. The short answer: Airplanes don't spin. Or, at least,
we prefer them not to -- especially on commercial flights. Dimples on a golf
ball help create a boundary layer of turbulent air that reduces drag when the
ball is spinning. A dimpled golf ball with backspin actually works like an airplane
wing, directing airflow downward and creating an upward reaction force, as per
Newton's third law of motion. With an actual airplane wing, though, you want
a smooth (or laminar) boundary layer. I'd need about 14 more paragraphs to nail
down the specifics.
And now for today's question: Are light bulbs luminescent?
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A WORD FROM THE PHOTOCHEMIST COMMUNITY
Answer to our previous question: Last time we asked you whether light bulbs
are luminescent. Contrary to what was stated earlier in this here very space,
no they're not. I am hip to this now thanks to an email from vigilant reader
and photochemist E. Morlino. (Whenever I get an email from a photochemist, I
know I'm in trouble.) Technically speaking, luminescence is defined as a low-level
emission of light by a chemical or physiological process. Light bulbs are actually
incandescent, which refers to light given off with intense heat. Morlino continues:
"Maybe a better question would have been: What is the difference between
fluorescence and phosphorescence?" Having looked into this, E., I must
say I have a profound new respect for photochemists.
And now for today's question: All together now -- what is the difference between fluorescence and phosphorescence?
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FLUORESCENCE AND PHOSPHORESCENCE
Answer to our previous question: Last time we asked you what the difference
is between fluorescence and phosphorescence. May as well start with Webster:
fluorescence: luminescence that is caused by the absorption of radiation at
one wavelength followed by nearly immediate reradiation usually at a different
wavelength and that ceases almost at once when the incident radiation stops
phosphorescence: luminescence that is caused by the absorption of radiation
at one wavelength followed by delayed reradiation at a different wavelength
and that continues for a noticeable time after the incident radiation stops
As you can see, what we have here is a difference in industriousness. Phosphorescent
light keeps on working after the whistle blows, so to speak, while fluorescent
light knocks off at 5 p.m. exactly. The fluorescent light tube actually utilizes
both types of luminescence. A stream of electrons is sent through the tube,
which is filled with a gas containing argon and mercury vapor. These electrons
excite the mercury atoms, which give off ultraviolet photons when they cool
down -- hence the fluorescence part. The photons, in turn, hit the phosphor
coating the inside of the fluorescent tube, creating phosphorescent visible
light.
And now for today's question: Are phosphorescent light tubes more efficient than incandescent light bulbs?
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LUMENS AND WATTAGE
Answer to our previous question: Last time we asked you whether phosphorescent
light tubes more efficient than incandescent light bulbs. Indeed they are. As
we discussed earlier, incandescent light bulbs are really just tiny little furnaces.
The thin tungsten filament in a light bulb becomes overwhelmed by the electricity
being passed through it, and incandesces into a white hot state. All that heat
is wasted electricity, since what we want out of a light bulb is light, not
warmth. A fluorescent light is around five times as efficient, in terms of electrical
wattage. An incandescent bulb produces about 15 lumens (a unit of measuring
light) per watt. A fluorescent light: 60 to 100 lumens per watt.
And now for today's question: Since tungsten is flammable at high temperatures in air, what gas do they use to fill the bulb?
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NOBLE GASES AND OTHER INERT GENTLEFOLK
Answer to our previous question: Last time we asked you what gas is used inside
incandescent bulbs. This question was sent in by that most stalwart and faithful
of readers, Anonymous. It's actually one of many follow-up questions to our
ongoing discussion of light bulbs, which many find illuminating. Let's tackle
it from the inventor's point of view. While developing the light bulb -- a long
term project, by the way, and not the flash of inspiration it is sometimes depicted
as -- Edison quickly realized that he had a problem. His filaments kept bursting
into flame when lit up. No problem, Edison says, we'll remove the air from the
bulb. No oxygen, no fire. Unfortunately, the vacuum created when the air was
sucked out often caused the bulb to implode. Edison, being the genius that he
was, figured out that by filling the air with one of the inert Noble gases --
such as argon -- you can prevent fires and solve the pressure problem at the
same time. The rest is history.
And now for today's question: what do the words Kaibab, Coconino, Supai, and Muav. have in common?
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CANYON FACTS
Answer to our previous question: Last time we asked you what the following words
have in common: Kaibab, Coconino, Supai, and Muav. Answer: They're all new lines
of sports utility vehicles coming out from General Motors next year! Of course,
we jest. These are actually names of particular strata of rock that are visible
in the Grand Canyon. More fun facts: The Grand Canyon is 446 kilometers long
(277 miles), 1.6 kilometers deep (around one mile), and varies in width from
less than one kilometer to 29 kilometers (18 miles.) The Grand Canyon was formed
over millions of years by the meandering Colorado River, and is home to a handful
of unique animal species, including the Kaibab squirrel and the pink Grand Canyon
rattlesnake. One final note--park rangers will yell at you if you stand to close
to the edge. I learned this the hard way.
And now for today's question: The Harvest Moon appears close to what equinox?
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HARVEST MOON AND EQUINOX
Answer to our previous question: Last time we asked you which equinox is closest
to the Harvest Moon. Like so many things in life, it depends on your hemisphere.
In the northern hemisphere, the Harvest Moon occurs nearest the autumnal equinox,
around September 22 or 23. In the southern hemisphere, the Harvest Moon occurs
in March, at the vernal equinox. The phenomenon is named as such because the
full moon at these times is particularly bright, and farmers would often bring
in the fall harvest under the light of the moon.
And now for today's question: Name the chemical substance that can be used to remove warts, prevent blindness, and develop photographic film.
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WARTS AND MIRRORS
Answer to our previous question: Last time we asked you to name the chemical
substance that can be used to remove warts, prevent blindness, and develop photographic
film. A rather versatile little chemical compound, pure silver nitrate burns
the skin and is poisonous if swallowed. Judiciously applied, however, it can
be used to burn off warts and even helps prevent blindness when used in a diluted
solution. What's more, many of the silver salts used in film processing are
made from silver nitrate. Oh, yes--and mirrors. Silver nitrate is used to make
them, too.
And now for today's question: Name the constellation that appears between the constellations of Auriga and Cassiopeia.
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ECLIPSING BINARIES!
Answer to our previous question: Last time we asked you to name the constellation
that appears between the constellations of Auriga and Cassiopeia. I'll give
you a hint. This is the constellation you'd want on your side if you were going
up against Medusa. Perseus, you'll recall, was the Greek hero who killed the
snake-headed Medusa and generally swaggered through the Mediterranian like he
owned the place. The constellation Perseus is notable for including the binary
star system Algol. This type of star system is called an eclipsing binary, because
the two stars revolve around each other is such a way that one periodically
blocks the light of the other. You can actually see the changes in brightness
with the naked eye.
And now for today's question: What famous scientist was investigated for former Communist associations by the Atomic Energy Commision in 1954?
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COMMUNISTS AND ATOM BOMBS
Answer to our previous question: Last time we asked you to name the famous scientist
investigated for former Communist associations by the Atomic Energy Commision
in 1954. J. Robert Oppenheimer directed the U.S. atomic energy laboratory in
Los Alamos, New Mexico, from 1943 to 1945, when the first atom bomb was designed
and built. Charges of disloyalty and former Communist ties led to an AEC investigation
in 1945. Oppenheimer was cleared of any charges, but also denied access to any
further secret information--standard operating procedure in the Red Menace years
of the 1950s. In 1963 the AEC awarded Oppenheimer its highest honor, the Enrico
Fermi Award, in part to atone for the investigation.
And now for today's question: Aurora borealis is the technical term for the phenomenon known as the Northern Lights. Name the equivalent term for the Southern Lights.
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THE SOUTHERN LIGHTS
Answer to our previous question: Last time we asked you to name the technical
term for the Southern Lights. It's fairly common knowledge, in the northern
hemisphere anyway, that the phenomenon we call the Northern Lights is also known
as aurora borealis. A similar phenomenon occurs in near the southern pole of
the earth, known as aurora australis. Both appear as arcs or sheets of light,
and can sometimes resemble a curtain moving tis the wind. They're associated
with the solar wind, a constant stream of electically charged particles emanating
from the Sun. When these particles interact with molecules in earth's upper
atmosphere, energy is discharged--some of it in the form of auroras.
And now for today's question: To calculate the circumference of a circle, you must multiply the diameter by what?
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TOTALLY IRRATIONAL NUMBERS
Answer to our previous question: Last time we asked you, to calculate the circumference
of a circle, you must multiply the diameter by what. Why, it's everyone's favorite
irrational number-- pi! Pi is simply the ratio of the circumference of a circle
to its diameter--approximately 3.14159. It's irrational, however, because it
can not be expressed as a fraction or a decimal with a finite number of decimal
spaces. Mathematicians, for which this kind of imprecision is like an itch you
can't scratch, have employed supercomputers to calculate pi out to millions
of digits. Still no end in sight....
And now for today's question: What is an eyewall? (A) a part of the retina (B) a part of a hurricane (C) a fish (D) an optical measuring term
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STORMS AND FISH
Answer to our previous question: Last time we asked you what an eyewall is (A)
a part of the retina (B) a part of a hurricane (C) a fish (D) an optical measuring
term. The answer is (B) a part of a hurricane. The eye of the hurricane is the
calm central zone that can be upwards of 35 kilometers in diameter. The eyewall
is the ring of storm clouds and turbulence around the eye, and is often the
most violent part of the storm. That's because the eyewall is the area in which
air pressure changes most drastically. Winds in the eyewall have been clocked
at greater than 320 kilometers per hour. Bottom line: Eyewalls are trouble.
Walleye, on the other hand, are a species of perch and actually very delicious
indeed with a little butter and lemon.
And now for today's question: The defect known as strabismus affects what part
of the body?
+++
THE EYES HAVE IT
Answer to our previous question: Last time we asked you what part of the body
is affected by the defect known as strabismus. Look into my eyes, gentle reader.
Strabismus is a defect in which the eyes are not working in conjunction. If
the deviated eye is turned in toward the nose, it's called cross-eye. If the
eye turns outward, it's known as walleye. When strabismus isn't treated early
enough, it can turn into a permanent condition--strabismic amblyopia, or lazy
eye. Then, of course, there's the particularly malicious condition known as
sinisterium jujuopia, or evil eye, most common in witches and warlocks.
And now for today's question: According to legend, what famous scientist was first to utter "Eureka!"?
+++
BATHTUBS AND GREEKS
Answer to our previous question: Last time we asked you what famous scientist
was first to utter "Eureka!" An enduring favorite among mad scientists
and overstimulated philosophers, "Eureka!" is traditionally believed
to have originated with ancient Greek thinker Archimedes. According to legend,
Archimedes is said to have shouted "Eureka!" ("I have found it!")
as he stepped into his bath. It's well known that many scientists do their best
thinking in the bathroom. In Archimedes' case, he realized that the volume of
an object can be measured by determining how much water it displaces.
And now for today's question: To what purpose did Archimedes initially and most famously apply his new insight?
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GOLD AND DENSITY
Answer to our previous question: Last time we asked you how Archimedes most
famously applied his method of determining volume. As legend has it, ancient
Greek scientist Archimedes is said to have shouted "Eureka!" as he
stepped into his bath and realized that the volume of an object can be measured
by determining how much water it displaces. It's said that around the time of
this discovery, there was some controversy among the Greek muckety-mucks as
to whether a golden crown was really made of solid gold. Archimedes, by determining
the crown's volume, then weighing it, was able to calculate its density. He
was able to conclude that the crown was not dense enough to be pure gold.
And now for today's question: Is steel a metal?
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STOUT ALLOYS
Answer to our previous question: Last time we asked you whether steel is a metal.
Well, technically speaking, steel is a metal alloy. An alloy is a material made
of two or more metals, or of a metal and another material. Steel is an alloy
of iron and carbon, and is a useful material in that its stronger than either
of its components. Brass is another example of an alloy stronger than its components
- in this case, copper and zinc.
And now for today's question: Why does the moon produce two high tides per day?
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MOONS AND TIDES
Answer to our previous question: Last time we asked you why the moon produces
two high tides per day. This is a follow-up to our previous discussion of the
moon's effect on tides. As we noted last time, the moon actually causes high
tide on both the side of the earth directly facing the moon -- and the other
on the side facing opposite. As the earth spins, and as the moon orbits the
earth, this results in two high tides per day (approximately) in most coastlines
on the planet. Several readers wrote in to ask why the moon effects tides on
the opposite side of the earth. Well, just as the moon's gravity pulls water
on the near side of the earth toward the moon, it also pulls the solid body
of the earth away from the water on the earth's far side.
And now for today's question: How many kilograms of rock have been brought back to the earth from the moon by astronauts? (A) 3.82 (B) 38.2 (C) 382 (D) 3,820
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CRATERS AND ROCKS
Answer to our previous question: Last time we asked you how many kilograms of
rock have been brought back to the earth from the moon by astronauts -- (A)
3.82 (B) 38.2 (C) 382 (D) 3,820. The answer is (C) 382 kg, or around 842 pounds.
Rocks from the size of small pebbles to huge building-size boulders are strewn
about the surface of the moon. This is due chiefly to the fact that the moon
is forever being pelted by meteorites. That's why the man in the moon has such
a pockmarked face - craters, you see. The moon has no atmosphere, so meteorites
that would otherwise burn up upon entry pretty much smack into the moon full
force.
And now for today's question: How many planets in our solar system have moons?
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PLANETS AND MOONS
Answer to our previous question: Last time we asked you how many planets in
our solar system have moons. I got burned on this the other night in Trivial
Pursuit, much to my chagrin. The answer is seven, as follows: (I forgot about
Charon.)
Mercury and Venus: None
Earth: The Moon
Mars: Phobos and Deimos
Jupiter: Io, Europa, Ganymede, Castillo
Saturn: Mimas, Enceladus, Tethys, Dione, Rhea, Titan, Iapetus, many smaller
moons
Uranus: Miranda, Ariel, Umbriel, Titania, Oberon, many smaller moons
Neptune: Triton, Nereid, many smaller moons
Pluto: Charon
And now for today's question: Who is the Java Man?
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THE AMAZING JAVA MAN
Answer to our previous question: Last time we asked you who the Java Man is.
Sometimes referred to as a barrista, the Java Man is a surly, overcaffeinated
species that thrives in coffee bars and espresso cafes around the world. We
jest, of course. The Java Man is the popular name attributed to a pile of bone
fragments found in Java in 1891. At the time, it was believed that the fragments
were the remains of the "missing link" between ape and man. The Java
Man has since been reclassified as a fossil of the extinct species homo erectus.
Anthropologists believe this early humanlike creature lived in Asia, Africa
and Europe for about half a million years, during a period just before the Ice
Ages.
And now for today's question: How is IQ determined?
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IQ AND AGE
Answer to our previous question: Last time we asked you how IQ is determined.
IQ, or Intelligence Quotient, refers to the ratio of the mental age, as determined
by tests, to the chronological age. (The ratio is then multiplied by 100 to
get rid of the decimal points.) In theory, an IQ test is supposed to measure
an individual's ability to solve problems, retain information, form concepts,
reason, and so forth. The problem is that no test has yet been developed to
gauge mental age that is not culturally biased. In fact, it's been demonstrated
time and time again that IQ tests reflect the cultural background of the persons
who set up the test. A broad, pop-culture demonstration of this can be appreciated
by watching an American try to play along with the British TV version of "Who
Wants to be a Millionaire?" I speak from experience.
And now for today's question: What causes jet lag?
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MYSTIC RHYTHMS
Answer to our previous question: Last time we asked you what causes jet lag.
A uniquely modern phenomenon, jet lag results from our newly acquired ability
to travel halfway around the world in a matter of hours. The trouble is that
our body's metabolism is governed by an internal clock that regulates things
in a 24-hour, day/night cycle. This is called a circadian rhythm, in case you
were wondering. When we travel long distances, we upset our internal clock,
throwing off various hormonal secretions regulated by our circadian rhythm.
This is the sensation of feeling 3 a.m. while everyone else is looking high
noon.
And now for today's question: If lepidopterans could appreciate theater, which show would they like best? (A) Oklahoma! (B) Madame Butterfly (C) South Pacific (D) Brigadoon
+++
BUTTERFLIES AND THEATER
Answer to our previous question: Last time, we asked you which show lepidopterans
would like best if they could appreciate theater: (A) Oklahoma! (B) Madame Butterfly
(C) South Pacific (D) Brigadoon. Making up the fourth largest order of insects,
lepidopterans are more commonly known as butterflies. (Moths, too, but butterflies
are the real marquee players here.) Lepidopterans are distinguished by four
wings covered with tiny scales and by the hollow, flexible tubes they use as
mouths. Butterflies and moths serve a crucial ecological function: They facilitate
the process of pollination, which helps plants reproduce. Basically, as they
hop from flower to flower looking for nectar, butterflies and moths get covered
in pollen, which they deposit onto the next flower. This sort of ecological
bed-hopping is evidently tolerated in nature; yet another shameful example of
general moral decline among insects.
And now for today's question: Have scientists really approached a few hundred billionths of a degree above absolute zero?
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KELVIN AND FAHRENHEIT
Answer to our previous question: Last time, we asked you if scientists have
really approached a few hundred billionths of a degree above absolute zero.
The answer is yes. Reader S. Korke recently forwarded a report from Brighton,
England, in which scientists have cooled a cloud of rubidium atoms to within
a few hundred billionths of 1 Kelvin. This is the latest update in our absolute
zero series, which has earned great popularity due to its fascinating subject
matter and the number of mistakes that have sneaked through. A few addenda from
previous reports: Absolute zero is most often identified as -273.15 degrees
on the Celsius scale, -459.67 degrees on the Fahrenheit scale, rather than the
-273.16 and -459.69 figures used in a previous tip. Also, the term "degrees"
is not used with the Kelvin scale. Finally, many readers have pointed out that
achieving true absolute zero is impossible, since it breaks fundamental rules
of thermodynamics. No argument here.
And now for today's question: Is the sun shrinking?
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THE INCREDIBLE SHRINKING SUN?
Answer to our previous question: Last time, we asked you if the sun was shrinking.
This question comes in from reader R. Henderson, who writes that he heard that
the sun shrinks five feet per day. The shrinking sun debate is a controversial
one, but as long as we're getting into it, the traditional line is that the
sun is shrinking five feet per hour, not per day. The figure comes from a study
presented to the American Astronomical Society in 1979. Creationists often cite
this as evidence that the earth cannot be as old as contemporary scientific
models suggest. The argument goes that if the sun is steadily shrinking at this
rate, and has been since the beginning of its existence, then it would have
initially been too large to allow life to evolve on earth. However, the 1979
report was preliminary, never published, and has never been verified. Most researchers
believe that the sun goes through cycles of expansion and contraction, but there
is no reliable evidence that the sun is steadily shrinking.
And now for today's question: name the three general classifications of rock.
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SPEED AND DEATH
Answer to our previous question: Last time, we asked you to name the three general
classifications of rock. According to my cousin Sal in L.A., rock can be classified
as heavy metal, speed metal, or death metal. But then, cousin Sal has been living
on Sunset Strip for the past decade and plays bass guitar for a band called
Constant Vomit. We, of course, are talking about minerals. The three basic classifications
of rocks are igneous, sedimentary, and metamorphic. Igneous rocks are made when
magma solidifies. Sedimentary rocks form over time when layers of material settle
onto one another. Metamorphic rocks form when existing rocks are subjected to
heat and pressure, then change while still solid. (I suggested to Sal that "Metamorphic
Rock" is a great title for an album, but he just grunted.)