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What we're seeing here are two solid-state Tesla Coils, each running in the 41 kHz range, performing a little concert thanks to some ingenious electrical work. The coils, which have been nicknamed the Zeusaphone, were developed by Tesla enthusiasts Jeff Larson and Steve Ward.

On his site, Larson explains that a particular version of this type of coil can be good for audio modulation because it produces several hundred sparks per second. The apparently continuous crack of light we see is actually a series of brief sparks. Larson and Ward figured out a way to modulate this frequency digitally, and get the sparks to crank out the sound waves or musical notes they want.

This concert features "Dance of the Sugarplum Fairies," but they've also done the theme from Super Mario Brothers and others. In terms of audio quality it doesn't quite measure up, but when you're talking pure spectacle, this has to be tops. You wonder if Tesla himself would be proud.—Gregory Mone

Even Michael Jordan would have to be impressed with this dunk. The athlete (?) in this very popular video clip apparently breaks the world-record for a trampoline-aided, long-distance dunk, soaring more than 20 feet before slamming it through. That's outside the college three-point line, MJ.

The secret to his success, according to physicist Len Fisher, an Ig Nobel winner who runs a website focused on the science of everyday life, is the leap forward towards the front of the trampoline, right before he flies to the hoop. He's not merely closing the gap here. In the middle of the trampoline, he's stretching all the springs on the outside equally, but once he moves to the edge, he really only stretches the springs closest to him. "The closer to the edge," Fisher says, "the more effective the recoil is going to be." And since he tilts his body forward, that recoil throws him horizontally.

The amazing thing, Fisher adds, is that he doesn't slip when he pulls off this switch between vertical and horizontal motion. You'd need incredibly high friction between your feet and the trampoline. Fisher wonders if he had some sort of resin that gave him a better grip. And the look of tension on the face of that guy with the glasses? Sorry, we can't explain that one. But it might just be the highlight of the whole clip.—Gregory Mone

Apparently classic cars aren't enough of a draw anymore. The Mercedes-Benz Museum in Stuttgart, Germany turned its smoke ventilation system into a spectacle, generating what the Guinness World Records organization is calling the world's largest artificial tornado. (See the November issue of Popular Science for an article about an engineer who thinks these man-made vortexes could be used to generate electricity.)

Though towering, the twister probably isn't dangerous. It's not going to suck up any bystanders, or cars. To create the effect, the museum's designers set up a disco smoke machine, then activated a set of 144 nozzles on the ceiling of the building's enormous atrium. The ventilation system, designed for emergencies, sucks the disco smoke up from below. To produce a spinning vortex, however, they blew air in from the sides, forcing the smoke to swirl.

The process took seven minutes, but the result, seen here, certainly looks capable of drawing crowds. Or making them run for their lives.—Gregory Mone

This little party trick is guaranteed to impress, and you don't need any special materials, just a decent freezer and a bottle of beer. Emory University physicist Sidney Perkowitz, the author of the forthcoming book Hollywood Science, says the phenomenon at work here is most likely supercooling - a process by which water can remain in a liquid state below its freezing point. It's a delicate balance, though, as the water will turn to ice given the slightest shock.

If supercooling is the culprit, the hidden scientist in this video most likely left the bottle in the freezer long enough for it to drop down below the freezing point - some other sites recommend about 30 minutes. Next, the shock of slamming the bottle on the table jolts the beer, and this added energy forces it to crystallize into ice.

Of course, it's hard to say for sure what's happening in this clip, and the many other frozen beer related videos posted on YouTube, because we don't have all the information. The best way to test the idea would be to try it yourself. I'd do the same, but I don't believe in waste.—Gregory Mone

This extended rubber-burning session was performed in honor of the classic Burt Reynolds movie Smokey & The Bandit, but NASCAR drivers are also prone to peeling out after a victory. So, what's at work here? We asked University of Nebraska physicist Diandra Leslie-Pelecky, the author of a forthcoming book called The Physics of Nascar, to tease out the science in the clip, and she says it's basically a big, loud, smoke-filled demonstration of the law of conservation of energy.

Normally when you step on the gas in a rear-wheel drive car, the front tires roll, and the car goes forward. Here, though, the driver also keeps one foot on the brake. The front end of the car is trying to stay in place by keeping its wheels locked, while the back end is trying to drive forward. Some of the energy the engine produces still goes into moving the car around that parking lot, but a lot of it is also lost to sound and smoke.

The asphalt itself eats away at the tires like sandpaper smoothing out a piece of wood. "You're seeing the person burning off their tires, basically," Leslie-Pelecky says. While this display is pretty impressive, NASCAR drivers produce even more smoke than this adventurous driver because their tires don't have tread. Since the tires are smooth, there's more material in contact with the track, so they burn more rubber, faster.

The final lesson? "If you try this at home," Leslie-Pelecky says, "You'll probably need a new set of tires."—Gregory Mone

You can't really expect good things to happen when a 305-pound football tackle's knee rams into an opposing player's head, but this clip from one of last Sunday's games is particularly chilling. In the video, Miami Dolphins quarterback Trent Green tries to block defensive tackle Travis Johnson as he pursues one of Green's teammates. The problem here is that Johnson is a very large and very fast man. Green realizes that throwing his 200-pound frame into Johnson's chest won't do much, so he tries to undercut the defender. Unfortunately, his timing is terrible.

As Green throws himself forward, Johnson's right knee comes up at the same time, slamming into the side of the quarterback's helmet. This is where inertia comes into play. Inside the skull, the brain is protected from minor impacts or jolts by a thin layer of fluid. In that instant after Green's head meets Johnson's knee, his helmet and skull stop moving, but his brain keeps going until it bumps up against the inside of his head.

The science of concussions is still being worked out, but there's some evidence that the momentary jarring of the brain affects blood flow. The good news: As Popular Science reported in our August issue, new helmet technology could enable scientists to get a better sense of the biomechanics of concussions, and aid coaches and trainers charged with determining whether or not a player should check back in after a mind-fuzzing hit.

For Green, though, this wasn't even a question. He was done for the day.—Gregory Mone

Robots are very good at doing the same thing over and over again, with ridiculous precision. They don't get bored and, as long as you keep the power on, they don't get tired, either. Still, it's pretty startling to watch the industrial arm in this clip toss in mid-range jump shots with such ease.

The arm, manufactured by a company called ABB and normally used on auto assembly lines, has been touring the country's science museums for more than ten years. Modified and programmed by a group at the Carnegie Science Center in Pittsburgh, PA, the robotic arm scoops up each basketball with two long metal rods, or tines. Then it executes one of a few pre-programmed motions—a scoop shot, a hook and a standard jumper—rolling the ball off those artificial fingers and tossing it skillfully through the rim.

But Tom Flaherty, the Director of Exhibits, Facilities and Operations at the Carnegie Center, spearheaded the development, says the robot isn't 100 percent accurate. Not because of a mechanical or software glitch. The robot runs through the same steps with each shot, but the ball itself can change. The robot is programmed to sink shots using a ball with certain specifications. If one of the balls is deflated slightly, its flight pattern might be different, and it might not slip through the net. Which really doesn't seem all that different than those NBA players complaining about the league's new basketballs at the start of last season.

Apparently all good shooters, men or machines, are picky.—Gregory Mone

This clip of a 4X4 speeding up a ridiculously steep face looks like a once-in-a-lifetime accident, but dune-climbing is actually a sport. Tens of thousands of people show up for events like this in the United Arab Emirates and other sandy locales. The driver of this vehicle undoubtedly has a serious combination of guts and skill, but apparently there's nothing all that special about the car

Hydrofoil surfing is just one of those things that doesn’t look right when you see it for the first time. These guys are surfing, riding down the face of a wave, and yet the board itself is more than a foot above the surface. Huh?

In this video, the foil is attached to the bottom of the board via a single strut. After a jet-ski pulls the surfers up to speed, allowing the hydrofoil to push board and rider up out of the water, they let go of the tow rope and let the power of the wave take control. Terry Hendricks, a physicist and long-time surfer who has designed an innovative wave-rider of his own, says the foil effectively acts like an underwater glider. When the surfers are coasting down the face of the wave, the water itself is rushing upward, getting sucked up by the energy of the swell. This rushing water acts like an updraft in the air, generating lift—only in this case it’s keeping the foil flying instead of a glider.

The real trick, though, is  balance. Hendricks compares the form of hydrofoil surfing practiced in this video to riding a unicycle. The rider is balanced over that single strut, and there are probably 30 inches between the bottom of the board and the foil below the water. His own model uses two foils, front and back, and a bodyboard approach. The rider lies down, kicking into the wave. This makes it easier to balance but produces a much bumpier ride, since the leading foil stays at water level. With the surfers shown here, on the other hand, the single foil is a good distance below the surface most of the time, so they’re completely avoiding wind chop, and smoothly cruising down the face of waves that look like mogul hills. Ready to try it out?—Gregory Mone

The nearly 6,000-foot-long Tacoma Narrows Bridge, known as Galloping Gertie, opened up on July 1, 1940, and collapsed just four months later. Winds reached 42 miles per hour on that fateful day, which proved too intense for the structure. There were a number of causes, but the basic problem was that engineers hadn't yet learned to account for wind loads in their designs. During the planning phase, the engineers reduced the proposed depth of the concrete and steel girders beneath the roadway from 25 to 8 feet. This loosened the stiffness of the road, and made it much more susceptible to wind. In fact, before the collapse, local residents had noticed that less intense gusts could cause the bridge to move. But those movements involved longitudinal waves – one end of the bridge rose, the other fell, in a less dramatic fashion than what we see in one of the early scenes in this clip.

Prior to the collapse, though, the wind induced torsional movement. In other words, the road started to twist. While the center line stayed stable, one side of the roadbed rose and the other dropped. When this twisting motion peaked, the sidewalk on one side was 28 feet higher than the opposite one.

Eventually, this twisting motion proved too much for the structure. The cables started to snap, and chunks of the bridge fell into the water below. Finally, the entire center collapsed. With this mass gone, the sections on either end sagged dramatically, dropping more than 40 feet. Nowadays wind-tunnel testing is fairly standard for bridge designs. When engineers drew up the plans for Gertie’s replacement, which has been standing for more than 50 years, you can bet they spent a lot more time factoring in the breeze.—Gregory Mone