If the top name in home pole-dancing equipment has anything to say about it, absolutely!
By Brett ZardaPosted 05.21.2008 at 3:56 pm4 Comments
There must be a God after all. Peekaboo Entertainment—creators of the Carmen-Electra-endorsed "Electra-Pole" home pole dancing kit—is reportedly planning to take their expertise to the Nintendo Wii. Adding another interesting dimension to the Wii's role as a fitness machine, the proposed pole dancing title could further ensure that men spend all day playing, or now watching, video games.
Shortly before our crazy biker pulls the reverse-Knievel—jumping far past the landing area instead of far short—we hear one of his compatriots shout, “You can go twice as fast!” This is a faulty hypothesis, as it turns out, but to the layman it would seem to make sense. After all, our biker had previously executed a graceful flop straight into the giant pit o’ foam. Doubling the takeoff speed intuitively should double the distance he flies, putting him a little farther into the pit but still within its bounds. Right?
Not exactly. Though it’s impossible to tell from the video exactly how much faster the biker was going on the second attempt, any increase in speed would be liable to have unforeseen consequences. That’s because the best way to understand how the bike flies is not with the concept of speed, but with energy. Why? Energy, as the lab coats like to say, is always conserved—and it’s gotta go somewhere. In this case, all the energy the bike carries into the jump is used to lift the bike however many dozen feet into the air before gravity puts it back into the speed of the freefall.
The funny thing about energy, though, is that it increases with the square of speed. That means that an object going twice as fast has four times as much energy, one going three times as fast has nine times as much energy, and so on. And practically speaking, four times as much energy means our biker is going to fly four times as high and sail four times as far. Exponents, like landing distances, tend to increase quickly. It’s important to make sure your foam can accommodate them. —Michael Moyer
Far be it from us to deride anyone’s childish fascination with blowing stuff up in a microwave—a foolhardy nerd rite of passage if ever there was one—and what better place to exhibit dangerous, potentially expensive shenanigans than YouTube? The experiment is simple. Take a seedless grape and slice it lengthwise, making sure (this part is important) not to cut all the way through, so you leave a little bit of skin connecting the two halves. Put it face-up in a microwave, and blam: fireworks!
So what the heck is going on in there? Grapes are chock-full of electrolyte, an ion-rich liquid (a.k.a. “grape juice”) that conducts electricity. Each grape-half serves as a reservoir of electrolyte, connected together by a thin, weakly conducting path (the skin). Microwaves cause the stray ions in the grape to travel back and forth very quickly between the two halves. As they do this, the current dumps excess energy into the skin bridge, which heats up to a high temperature and eventually bursts into flame. At this point, the traveling electrons arc through the flame and across the gap, ionizing the air to a plasma (which itself can conduct electricity) and creating the bright flashes you see.
And that notion about poisonous gas tainting your roommate’s Hot Pocket? Well, the guy’s talking about the ozone generated when the air inside the glass is ionized. “Poisonous” might be too a strong word in this scenario (a little ozone definitely won’t kill you), although high concentrations of ozone can oxidize lung tissue and have been known to cause asthma in urban inversion-bowls like L.A. and Mexico City.
Again, DON’T TRY THIS AT HOME. Microwave ovens + biological capacitors = bad news. —Martha Harbison.
The electrons in metal are the worker ants of electricity: ubiquitous, able to work together to carry great loads, and free to roam in any direction. Since they’re unbound to any single atom or molecule, they can swim through the metal and move charge from one place to another. Air, on the other hand, lacks these mighty swimmers. All its electrons are held tight to their parent molecules. If you want to get air to conduct electricity like a metal, you have to pull those electrons away—and pull real hard.
That, in effect, is what the 500,000 volts in this switchyard are doing. When the circuit breaks at the beginning of the clip, the electrical field between the contacts is so strong that it yanks electrons free from the nitrogen and oxygen in the air. These electrons flow uninhibited between terminals as if they were in a metal and allow the air—now acting as a plasma, not a gas—to conduct electricity. It’s the same thing that happens in lightning, except lightning is one quick burst of energy from cloud to ground. Here, we’ve got a power plant spitting out energy to spare. Electricity tears the air apart so that it can flow through the cracks.
Unsurprisingly, all this activity heats the air pretty quickly. That’s why the arc—the area of lowest resistance, where the electrons can be freed from their host molecules—moves up. Hot air rises, after all. —Michael Moyer
Though A-Team reruns would have you believe otherwise, vehicles that crash in real life aren’t immediately and inexorably consumed by giant explosions. Any movie geek knows this. Gasoline doesn’t explode—it burns, just like wood—except in the uncommon environment of an internal combustion engine. Yet our unlucky racer’s motorcycle blows up with such vigor, you’d think Michael Bay placed the explosive charges there himself. So what gives?
The answer lies in the way the bike tumbles across the racetrack. Take a close look at how it flips before conflagration. The first time the bike bounces off the ground, the force seems to knock the cap off the gas tank. As the bike flips again, you can see racing fuel spray out of the top of the tank in great arcs, billowing through the air along with the dirt and gravel kicked up by the skid. This, as they say, is a bad sign.
Gasoline, like every other fuel, needs oxygen to burn. Ordinarily, if you were to set a match to a pool of gasoline, only its surface would burn, because only its surface would be in contact with the oxygen in air. But as it’s injected into your engine, the gasoline is atomized (imagine a tiny gasoline spritzer set on “mist”) in order to thoroughly mix the fuel with air before your spark plug ignites the combination. Since every bit of nearby fuel is now surrounded by oxygen, this flame spreads almost instantaneously through the combustion chamber until everything is alight.
But in the case of the motorcycle explosion, the bike’s acrobatics did the work of atomizing the gasoline. Once a spark ignited the little droplets, the whole thing went up in a bang. So a word to the wise: If you’re going to have a catastrophic accident in a motorcycle race, try to keep your gas cap on. —Michael Moyer
Physics has given us a great many simple principles that make it easier to understand what’s going on in the world, some better-known than others. To wit: Every action has an equal and opposite reaction; what goes up must come down—both classics, for good reason. And the blingiest of the axioms, E=mc², is particularly useful for understanding why a fistful of plutonium can cause such a big bang. Less famous but far more important on a day-to-day basis if you’re an SUV designer, a high jumper or—as in the present case—a crane operator, is the principle that any object will behave as if all its weight is concentrated at its center of mass.
Finding an object’s center of mass is fairly simple. It’s the point at which half the mass is above the center and half below, half is on the right and half on the left, and half is in front and half in back. If you stand straight up with your arms at your sides, your center of mass is a little below your bellybutton (unless you’re J. Lo). But here’s the important part: If your center of mass is not above your feet, you’re going to fall over. The same principle works for a crane. If the center of mass of the total system—crane plus whatever it’s carrying—moves to one side of the crane’s base, the crane will tip.
As our crane lifts the bus out of the water, trouble is a-brewin’. The water itself is holding up the partially submerged bus. (Remember Archimedes? No? Here: Water pushes up on an object with a force equal to the weight of the water being displaced—this is the reason things feel lighter in water.) As the bus leaves the river, the crane takes on more of its weight until the center of mass shifts so far away from the crane’s arm that suddenly there’s a tip, a splash and the call for a bigger crane. —Michael Moyer
