Mars mons: Try space mountaineering
DRAWING BY DEBORAH DERR McCLINTOCK
Q. You x-treme mountain climbers out there, where might you go to ascend to heights well beyond the peak of Mt. Everest? -J. Krakauer
A. Try a rocket to Mars! Some mountains there are higher than Everest's 9 kilometers, such as Olympus Mons (after Mount Olympus, home of the ancient Greek gods) at 25 kilometers, largest known (extinct) volcano in the solar system. What limits the heights of mountains on Mars, here, or anywhere is the planet's gravity, which causes the mountain to have weight, says Jearl Walker in The Flying Circus of Physics, With Answers. At too much weight, the overloaded base would liquefy, causing the mountain to sink somewhat. Thus there is a certain critical maximum height a mountain can reach, depending on the heavenly body where it's located.
If you (would-be) summiteers ever did manage to get yourself and your gear to Mars and to the base of Olympus– 700 kilometers across or about the size of Arizona– it would be a long trek for you but not a steep one: The mountain slopes up rather gradually at 6 degrees– perhaps drivable if you've packed your Rover. Already, some members of the British Interplanetary Society are making their own plans for mountain climbing on Mars.
Q. Baseball fans know there hasn't been a .400 hitter since Boston Red Sox slugger Ted Williams hit .406 in 1941. Yet from 1900-1940, seven different players broke .400 a dozen times. So where have all the .400 hitters gone? Are today's players getting worse? –K. Watt
A. Actually, they're getting better, said Stephen Jay Gould, author of Full House: The Spread of Excellence from Plato to Darwin. The average batting average has never changed much, staying around .260, reflecting the league balance between hitting and pitching. As hitters have gotten better, pitching has gotten better, maintaining the balance. And as everyone gets better, a surprising thing happens: The range of variation shrinks. In 1910, when Ty Cobb played, the average level of play was so much worse that Cobb could feast off the poorer pitching, etc., and in comparison to everyone else at the time, he came out at .420. But those days of "feasting" are long gone.
There are other theories, involving night ball, grueling travel schedules, changed ballparks, etc. But these lack Gould's elegance of explanation: Since Ted Williams' last-hurrah year, the bell-curve distribution of player performances has shrunk toward the median, eliminating the right-extreme of the graph and along with it today's would-have-been .400 hitters.
Q. You know of woodwinds, strings, brass and percussions from the Western symphony orchestra. What are aerophones, chordophones, idiophones, membranophones and electrophones? –P. Casals
A. They are the five Hornbostel-Sachs classes of musical instruments. This newer division is based on the physical characteristics of the sound source, making the categorizations more scientific, says David Crystal in The Cambridge Encyclopedia of the English Language.
Aerophones have their sound generated by vibrating columns of air within, such as brass, reeds, woodwinds; chordophones include stringed and some keyboard instruments; idiophones generate sound with the instrument body itself, such as bells, the triangle; membranophones are drums, tambourines, etc; the newcomer electrophones add synthesizers, electric guitars and the like.
Most enthnomusicologists now prefer this system since it is broad enough to encompass "instruments" from anywhere in the world–panpipes, music boxes, maracas, carillons, conch shells, guiros, jaw harps, even bull-roarers, washboards and toy spinning tops.
Q. What can make your car such a big air drag, costing you gas mileage and money? –H. Ford
A. Start with speed squared (speed x speed), a bleeding gas hole as the pedal hits the metal, says Barry Parker in The Isaac Newton School of Driving. Vehicle frontal area is another factor, obviously best when kept small, and frontal areas have certainly shrunk since the 1950s– unless you're SUVing or VANing or TRUCKing it.
How low can drag get? Ideal aerodynamic shape for cars is the teardrop, or fish– drag coefficient of about .03 to .04– best if the streamlines follow the car's contour from front to back without breaking away, though this rarely happens. Instead, turbulence! Typically, the onrushing air splits at the front bumper, some going over the vehicle and some under. The air over splits just before the windshield, then rejoins and rushes over the roof, possibly splitting again at the roof's end. Or it may leave the car smoothly. The wake behind can also be a drag, worse when the car's end is cut off, called "bobtailing."
Underside drag is another problem, says Parker, as are radio aerials, mirrors, wipers, door handles, wheels and internal drag from air going through the car. And this doesn't even factor in the car's "skin friction" and "rolling friction"– but perhaps you're out of gas by now.
Send Strange questions to brothers Bill and Rich at firstname.lastname@example.org.