Question: A new neighbor out on her driveway tells you she's washing and waxing her Porsche 924 Turbo to get better gas mileage. Isn't this the dumbest thing you ever heard?
Answer: Better check out her Harvard bumper sticker before saying anything. Maybe she's an engineering student who does a lot of high-speed driving, and just maybe she's laying a little tongue-trap for you.For there may well be a slight fuel-savings factor at high rates of speed, says Steen Sjolander, mechanical and aerospace engineer at Ottawa's Carleton University. Air drag is at least partly related to surface frictions against the car body. Streamlining helps, as when dust and squashed bugs are scrubbed away and small pits and scratches are wax-filled to reduce air turbulence and enhance efficient flow.
Speeds are critical here: At city speeds of 50 km/hour, the Porsche would lose only 1.3 horsepower to air drag, but at 200 km/hour, 85 horsepower are lost. Actually, surface finish accounts for only a little of this loss, with most stemming from the large turbulent wake behind the car, plus smaller wakes behind protrusions such as side mirrors.
So the car washer who drives at German autobahn speeds might notice a small fuel consumption effect, but probably less than comes from keeping tires properly inflated.
Question: Is it true you can stand a raw egg on end at the vernal or autumnal equinox? On these two days, it is said, gravitational forces balance out because the sun is directly over the equator.
Answer: Given a steady hand and the right egg with little bumps that act as pods, you should be able to pull this off any day of the year, says Tel Aviv University astronomer and astrophysicist Noah Brosch. The position of the sun has nothing to do with it.
Factors such as egg shape, wind currents, floor vibrations, etc., would dwarf the sun's forces on the egg. Besides, if the equinox stuff were correct, you'd need to be located right on the equator.
If you have trouble egg-standing, try sprinkling salt on the table first, then gently blow away telltale grains around the base. The salt cubes act as tiny props.
Question: What would life on Earth be like if there were no moon?
Answer: So different maybe there'd be no intelligent life here to pose the question, says Penn State University geoscientist James Kasting.
Calculations by French astronomer Jacques Laskar show that without the moon, Earth's tilt in its orbital plane would vary chaotically from 0 degrees to 85 degrees over tens of millions of years. The current tilt is 23.5 degrees, and it is this tilt that gives rise to the seasons. The tilt varies from 22 to 24.5 degrees over a time scale of 41,000 years and may help account for the coming and going of ice ages over the past 3 million years, says Kasting.
If the tilt got up above 35 or 40 degrees, summers would become extremely hot and winters extremely cold. Whether or not advanced life, including humans, could have evolved under such climatic extremes is unclear. So the moon does much more than merely light up the night sky. It's an important stabilizing influence on Earth's climate.
Question: Can you drive a golf ball roundly off a tee? Then maybe you're game for this classic hustle, made famous in the Roaring Twenties but good for a replay anytime.
Answer: You wager you can hit a 500-yard shot, a la a famous bet between '20s high-rollers Titanic Thompson (legend has it he secured a lifeboat spot on the ill-fated voyage by dressing as a woman) and Arnold the Brain Rothstein, of Chicago Black Sox Scandal fame, recounted in Harry Anderson's "Games You Can't Lose."
If your friend is wily, as was Rothstein when Thompson, a gifted golfer, proposed the shot, then a stipulation may be added that this be done all on a level surface. No problem, as Thompson soon proved by taking the shot to an icy shoreside golf course in February and driving a shot across the frozen surface of Lake Erie. The ball reportedly didn't stop until the April thaw.
Send STRANGE questions to brothers Bill and Rich at firstname.lastname@example.org.