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So you want to know about lock picking?

There is this wonderful site that has a great article about it: http://home.howstuffworks.com/lock-picking.htm

I hate to be a cynic, but I think the whole point of news reporting is to attract your attention to those crucial 8 minutes every half hour... the commerical sponsors.

What happens inbetween commercials only exists to get you to turn to their channel... after all thats why (1) products like TIVO scare the crap out of them for its ability to hide commercials, and (2) product placement in the shows themselves allows commercial time to blend with content time. Hell, CBS was running programs about books that the parent company published, and calling it news... And after all, why are the news readers so pretty... so you'll tune in.

This is also why I believe news reporters tend to become politically biased over time towards their local markets... it is their job to retain viewers/customers, and so you preach to your local markets. The political landscape is strongly correllated with urban concentrations, as are the "big" markets. The "old" big 3 broadcast media meets the needs of the cities, with its liberal leanings. Those living away from urban areas have to rely on cable and satelite, which "new" big media promptly cornered the market, and tilted their content towards their libertarian/conservative consumers. The people like like Jennings's leanings will tend to flip on ABC, and ABC gets viewers to watch its commercials, and those of the other leanings will flip on Fox, and Fox gets viewers for its commercials. Companies win, educating citizens loses.

The amount of wobble has nothing to do with the degree of circularity of the orbit. Our Sun wobbles quite a bit, in fact. The gravity of Jupiter causes the center of the Sun to move in a circle with a diameter of approximately 1 million miles. That's more than 1 part in 100 of the distance between the Earth and the Sun -- easily detectable.

Not really, it's also used as a way to charge electric cars, and uses inductive coupling to transfer power. You can find a description and some pictures here. There's likely other applications on the market.

And weren't there some research projects using microwaves to power high-altitude planes or low-orbit satellites?

Not really, it's also used as a way to charge electric cars, and uses inductive coupling to transfer power. You can find a description and some pictures here. There's likely other applications on the market.

And weren't there some research projects using microwaves to power high-altitude planes or low-orbit satellites?

You have absolutely no idea how a fuel cell works, do you?

Try reading here or here for starters.

Fuel cells are not gas cans, and you will certainly not be pouring gasoline into your laptop battery. Please, read before you post.

Regarding the alkaline battery charger, someone correct me, but doesn't an alkaline battery use acid to corrode a piece of metal inside the battery to produce the chemical reaction needed to produce electricity?

No, you're thinking of an acid battery (such as the ones commonly found in automobiles). A lead-acid battery is actually rechargeable, so long as the lead doesn't get completely dissolved by the sulphuric acid.

On the other hand, an alkaline battery such as the AAA batteries commonly used in pagers, does not contain any acid. It's got zinc electrodes and some sort of magnesium powder in there. Go ahead and break one open -- you'll see the black powdery stuff, the long silvery core, and the cardboard that insulates the two poles from each other.

See also, How Stuff Works

It probably wouldn't be that practical, but it could be effective to dehydrate certain parts of someone's body by moving the water around inside. Maybe the military could find use for that.

Yeah! Then maybe someone could find commercial uses for this revolutionary new technology -- If light can move water around in a person, imagine what it could do to food! OH the possibilities! Wow, you could even have instant, ready-to-eat meals heated by this device! I better patent this idea of water-moving light quick before someone else steals it!

Well, actually they already have that-sort of. The Apache attack helicopter uses a targeting system that aims based on what the pilot looks at. Except that it uses a monocle over the right eye of the pilot. The monocle displays targeting information and presents a cross-hairs to the pilot. The pilot merely puts the cross-hairs on his target by turning his head and "looking" at it with the monocle and then pressing the trigger for the appropriate weapon. However, it's not REALLY based on what his eyeball is focused on, it's what the cross-hairs are pointed at. He could point the monocle towards the horizon and without moving his head, he could rotate his eyeballs to look down and fire, but unless he moves his head, the guns/missiles will still fire at what the monocle is pointed/looking at. Here are just a few pages that a quick Google search turned up: How Apache Helicopters Work-Controls and Sensors or "PBS-Frontline or this page that talks about the M142 INTEGRATED HELMET AND DISPLAY SIGHT SYSTEM (IHADSS)specifically.

Well, actually they already have that-sort of. The Apache attack helicopter uses a targeting system that aims based on what the pilot looks at. Except that it uses a monocle over the right eye of the pilot. The monocle displays targeting information and presents a cross-hairs to the pilot. The pilot merely puts the cross-hairs on his target by turning his head and "looking" at it with the monocle and then pressing the trigger for the appropriate weapon. However, it's not REALLY based on what his eyeball is focused on, it's what the cross-hairs are pointed at. He could point the monocle towards the horizon and without moving his head, he could rotate his eyeballs to look down and fire, but unless he moves his head, the guns/missiles will still fire at what the monocle is pointed/looking at. Here are just a few pages that a quick Google search turned up: How Apache Helicopters Work-Controls and Sensors or "PBS-Frontline or this page that talks about the M142 INTEGRATED HELMET AND DISPLAY SIGHT SYSTEM (IHADSS)specifically.

The flash capacitor is about 4kV, not 12V.

No, no. While it's true that 4kV appears in the system, it's only for a brief moment, and doesn't get stored in a capacitor. It comes from a secondary transformer, and creates a pulse when the trigger is pressed.

The flash capacitor (the large can) is typically 330V, but in studio flashes (line powered, not point-n-shoot) it can be more. I'm tired of seeing wide-ranging, erroneous voltage quotes on Slashdot, sigh.

The 4kV comes from the _pulse_ that is sent to the flashbulb to make it conduct. The 300-odd volts are already connected to the ends of the flashbulb, and the 4kV pulse's purpose is to ionize the gas inside the flashbulb so that it conducts, allowing the capacitor to discharge.

See this for more detail.

Trust me, I've got almost ten of these things that I'm working into a project. I've shocked myself too, but never suffered anything more serious than a spasm.

Octane certainly is not a made up term - its a made up scale, and a real chemical. Isooctane is defined as having an octane rating of 100 on this scale. And nobody ever tests octane at gas stations.

It's pretty obvious you've never done anything but work at a gas station, isn't it?

However, you can steal energy from planets using gravity assists. JPL is amazingly good at doing these.

<tinfoilhat> We do need to worry that JPL is slowly robbing orbital energy from the planets they use. I've been worried about our profligate use of this irreplaceable resource for a long time. Worse, JPL seems to be totally blase about using Earth as one of their prime engines- enough gravity assists and the earth will fall into the sun!

Join the League to Conserve the Angular Momemtum of Planets today!

GNU has one, it's called HURD

Named for part of the stalk of the cannibas plant, notwithstanding whatever those hippies try to tell you about the meaning of the name.

Time for the dentists who haven't to switch over to using the radio. http://entertainment.howstuffworks.com/music-royal ties7.htm The radio stations pay the royalties...

Tapping on the lid doesn't even do anything for normal cans. Wait, yes it does. Hold on, no it doesn't. Shit, I don't even know.

Here is the answer to your question: "How the president didn't win the last election?"

"Hemi" is an old type of engine and it is an ad campaign. It sounds to me like you bought into the hype on tv.

From the first link:
"It was once called the "finest engine of its kind in the world," the Hemi Magnum engine once ruled the track and the streets. If your muscle car had the Hemi under the hood, very few other vehicles could beat you off the line. They had that much power. But when the oil crisis of the 1970s hit, the Hemi lost its luster. Sure, it was still fast, but it wasn't as fuel efficient as other engines, especially the ones produced by Japanese auto makers. So Chrysler shelved the demon and moved on to more civilized ideas like minivans."

From here:
"If HEMI engines have all these advantages, why aren't all engines using hemispherical heads? It's because there are even better configurations available today.
"One thing that a hemispherical head will never have is four valves per cylinder. The valve angles would be so crazy that the head would be nearly impossible to design. Having only two valves per cylinder is not an issue in drag racing or NASCAR because racing engines are limited to two valves per cylinder in these categories. But on the street, four slightly smaller valves let an engine breathe easier than two large valves. Modern engines use a pentroof design to accommodate four valves.
"Another reason most high-performance engines no longer use a HEMI design is the desire to create a smaller combustion chamber. Small chambers further reduce the heat lost during combustion, and also shorten the distance the flame front must travel during combustion. The compact pentroof design is helpful here, as well."

Also.

"Hemi" is an old type of engine and it is an ad campaign. It sounds to me like you bought into the hype on tv.

From the first link:
"It was once called the "finest engine of its kind in the world," the Hemi Magnum engine once ruled the track and the streets. If your muscle car had the Hemi under the hood, very few other vehicles could beat you off the line. They had that much power. But when the oil crisis of the 1970s hit, the Hemi lost its luster. Sure, it was still fast, but it wasn't as fuel efficient as other engines, especially the ones produced by Japanese auto makers. So Chrysler shelved the demon and moved on to more civilized ideas like minivans."

From here:
"If HEMI engines have all these advantages, why aren't all engines using hemispherical heads? It's because there are even better configurations available today.
"One thing that a hemispherical head will never have is four valves per cylinder. The valve angles would be so crazy that the head would be nearly impossible to design. Having only two valves per cylinder is not an issue in drag racing or NASCAR because racing engines are limited to two valves per cylinder in these categories. But on the street, four slightly smaller valves let an engine breathe easier than two large valves. Modern engines use a pentroof design to accommodate four valves.
"Another reason most high-performance engines no longer use a HEMI design is the desire to create a smaller combustion chamber. Small chambers further reduce the heat lost during combustion, and also shorten the distance the flame front must travel during combustion. The compact pentroof design is helpful here, as well."

Also.

Bah!! If this was true, why haven't we started mining asteroids "by now"?? Scientists theorize that there can be Trillions of dollars worth of raw materials within a single near-earth asteroid. A new theory proposes that Neptue and Uranus rain diamonds. Why hasn't deBeers jumped all over this? If Mars were gushing oil, it's still cheaper and easier to get it from Earth, just like our other resources.

I'd love to be able to press a button and jam their conversation, especially as most are conducted at about 40db.

radiocarbon dating is reliable out to about 60,000 years - http://science.howstuffworks.com/carbon-142.htm. The error increases, the older the samples are. I think radiocarbon dating can do + or - one year for up to several thousand years ago.

Right here
Mozilla has come a long way since it stomped its way into the Open Source realm. It was awarded "Best of 2003" in the Web browser category by PC World magazine.

How about comparing modern day cars, trains, busses, and planes, on a per-passenger basis?

According to Top Gear a few nights ago, trains get worse mileage than the average car, per passenger(I'm trying to find any info about the study online to see if that's based on maximum capacity of each type of vehicle or real-world average passenger counts) and a high speed train gets worse mileage than a jumbo jet!

For freight there's no doubt that diesel locomotives are the winner. Diesel locomotives are hybrid vehicles: a 2-stroke diesel generator, but electric motors. They are very efficient at moving large loads, not so good at light loads due to the weight of the loco itself (something like 135 tons). That's why passenger trains tend to be purely electric - to keep the huge weight of the generator off the train.

Here are some links:

HowStuffWorks article on diesel locomotives.
A CN Railroad page claiming a diesel locomotive can travel 3.5 times further than a truck on a gallon of fuel (presumably pulling equivalent loads).
A BNSF Railroad page claiming fuel efficiency of approx. 750 GTM (gross ton miles) per gallon. Most high efficiency cars would probably weight a ton or less so a 50 MPG Prius would be about 50 GTM per gallon.

1. Burning fuel and turning it directly into mechanical power. 20 percent efficiency.

2. Burning fuel; converting it into electricity (40% at a power plant); storing the electrical voltage in a battery (possibly a fuel cell) (90%); convert the battery power into mechanical power (72%). .40 x .90 x .72 = 26 percent efficiency.

It's close. One thing's for certain: fossil fuel cars are inseperably tied to oil. I'm for fuel cell cars, because that would mean more options for the consumer, and more competion.

reference

A Stirling Engine, perhaps? Nah, the weight would probably lose the extra efficiency you gain. If they're using an internal combustion engine, it's hard to say what would be best... you get better efficiency when you burn at higher pressures, but the higher the pressure you want to burn your fuel at, the heavier your engine will be.

I didn't mean to insinuate that it is difficult to take over an ISP (ours had a server owned about once every four months, and we weren't a windows shop), but rather how easy it is to tap, as well as otherwise modify, a phone line. As Mitnick proved, it's easier to convince the phone company to switch a line or add a tap for you than it is to do the legwork yourself.

How about rigging it up to a stun gun so when you get "hit" you really go down.

You wouldn't trust a public terminal, but you could probably trust a public power supply so you don't need to carry around batteries. People already trust public wifi networks ala Starbucks. CPUs and memory can continue to shrink, but what about keyboards and screens?

Keyboards can be embedded in cloth which could be rolled up. Displays could be made to be rolled up also (1, 2, 3). People are working on non-volatile nanotube-based memories which could replace bulky, fragile hard disks. Cool, zero boot-up time.

It's pretty reasonable to imagine that in five or ten years there could be a cheap computer with the feel and durability of thick cloth, that rolls up to be about 6 inches long and maybe an inch wide. Maybe you velcro it around your forearm when not in use. I'd buy one.

A few suggestions:
How Stuff Works has a good section on auto technology explaining the basics.

There are tech talk discussion forums where you can ask questions at many magazine websites. My current favorite is the 'Combustion Chamber' at Auto Week, and aside from the registration it is free. (If you find anything better, please let me know.)

One thing to remember about Horsepower TV is that they focus on a lot of muscle cars with pushrod engines. I personally am a big fan of pushrod engines (there are lots of pushrod vs. over head camshaft discussions on various forums), but the valvetrain layout is different enough from overhead cams that you can get confused comparing the two.

A lot of the hot rod magazines have free tech articles that give explanations on the magazine website.

After all, if vinyl is such a high-density storage medium, where are the vinyl videodiscs with 6-track sound?
Well, it might not exist, but if it were to, it would be a cross between Vinyl Video and an enhancement to Quardophonic audio

no? then what's this?

/nova20

Someone will correct me if I'm wrong, but i'm pretty sure gamma radiation doesn't get spewed out by the sun

The sun produces a TON of gamma radiation

at least not to that distance...

Sure, the inverse square law applies and all, but what else does distance have to do with it? Do you think the gamma radiation gets tired after awhile and decides to turn around and go home?

Maybe this will help? I can't really think of a simple way to explain it. They're a lot of fun to play with, though. :)

So that's why the space shuttle has such slow computers!

Emm, I'm digging now, ehh; why not sew my lips shut too. I can whistle a tune without paying royalties.

Wrong bucko! You get in the line with those law breaking litte tarts! There won't be anyone singing any songs around here without paying up. And we're expecting a check from your next Birthday party too!

Patents for an idea makes sense, in part, when an inventor wanted to protect his or her ability to profit or control the result of their effort. Patents and intellectual property protections were designed to prevent people from using your idea or effort to their betterment at your expense.

You're putting the cart before the horse. Patents and Copyright were not introduced in order to protect the business interests of inventors or authors, this was only the means. The ends were to encourage more innovation, as outlined in Section 8 sentence 8 of the US Constitution:

The Congress shall have power (...) To promote the progress of science and useful arts, by securing for limited times to authors and inventors the exclusive right to their respective writings and discoveries;

These rights (patents, copyright, trademarks and trade secrets, which are only contractual) are now being gathered under the collective, misleading name of intellectual property, in an effort to bypass the original justification of these rights, formerly referred to as exclusivity rights, in order to turn the means into the ends.

So first there were exclusivity rights, which were meant to serve the public, and whose benefits to the inventor/author (or rather, the patent or copyright owner) are merely incidental. Now justification and means are to be reversed. Intellectual property is meant to serve the rights holders, and benefits to society are merely incidental. More importantly, it does not even matter if society as a whole suffers from IP legislation. Logic patents and copyright are or are now intended to be perfect instruments of power for corporations. Large stashes of patents allow large software companies to lock out competition by smaller companies, and monopolize markets. Likewise, large music labels, which now are the copyright holders to almost all songs they release, are successfully lobbying for ever more severe copyright laws in an effort to shut down alternative promotion channels like P2P and independent internet radio stations. The big labels are afraid that, while airwaves are scarce and can easily be controlled by payola, Internet traffic is basically unlimited in range. You cannot have 500 national radio stations since the frequency bands are limited, but you can easily operate 5000 Internet radio stations without any bandwidth collisions. Incidentally, while the RIAA claims to have suffered massive losses due to Internet "piracy", many independent labels have experienced benefits from increased promotion of their music via P2P and other channels such as (the former) mp3.com and independent internet radio.

I see the intellectual property movement as part of a general neoliberal self-referential justification of capitalism, where the original goal of improving living conditions for the population is increasingly irrelevant. Today's capitalism is intended to be implemented for capitalism's sake, not because it would make lives of men better as compared to marketplace economies with a stronger balance between public and private property. The manipulations of the Californian power market, or the privatization of water supplies into monopolists' hands in South America are just two examples of many.

There are so many many variations possible when driving, that 2 trips hardly counts as a test case. A/C, out door temperature, speed limit, construction delays, stops, traffic, change in air pressure, passengers, tire air pressure, temperature of fuel, humidity, rain on the road, wind speed and direction. And yes these will all give variations - some more then others of course.

In fact just filling up the tank can give you variations - how do you know how accurate your gauge is? I can overfill my tank by 5 gallons, it won't register on the needle (still just F), but the fuel is there. The temperature of the gas can change how much volume equal amounts (mass) of fuel will take. Colder temperature you'll get more gas in the tank.

But octane will not make the slightest difference in milage for a vehicle that is designed for 87. If your vehicle is designed for 92 or can advance the timing then maybe - but then you are not supposed to use 87, so again not a comparision.

Howstuffworks "What does octane mean?"
Federal Trade Commission: Are you tempted to buy a high octane gasoline for your car because you want to improve its performance?
You can find more links on your own.

They also depend on what gas you put in the car. Some cars do drive better on supreme.

Higher compression engines, or more highly-tuned engines, need higher octane gas. Mostly, it's to prevent knocking (early detonation caused by compression rather than spark). Any good car of relatively recent make (at least the past 10 years, if not older) will have a knock sensor to adjust for lower-octane gas, at the expense of fuel usage. However, if your car is designed to run on 87 octane, higher test gas shouldn't make much of a difference.

Possibly this also has to do with the mountainous terrain and the fact that the gas gave me more power - not sure

Actually, there is less energy potential per gallon in higher octane gas than lower. That's not really an issue, though. What most likely happened was that previously you were not using the proper octane-level gas for your engine's compression and the ECM was adjusting to a less optimal program to compensate. As a side note, race gas and airplane gas have much higher octane ratings due to the use of lead additives. Don't try this in your car. Lead will kill your cats in a matter of minutes, not days or months. Race cars and airplanes don't have catalytic converters.

I do know that I regularly stick injector-cleaner in, so I shouldn't be getting plugged there. Therefore, I'm willing to state that better gas can give you better milage (and not all gas stations give the same quality gas either)

First off, most additives are snake oil. Pretty much the only thing that works is Techron (and knock-off brands using a similar formulation). If you fill your car at a station with Techron or a similar cleaning additive, there's no reason why you should have to add injector cleaner on your own. If you must, an application once or twice a year is sufficient. Any more often and you're just throwing money away. As for better gas giving you better mileage, that's true up to a point. As I mentioned already, higher compression engines require higher octane fuels. If you're not using the right fuel, your engine will operate inefficiently. Using a higher octane gas than is required is useless if your car can't adjust its compression ratios to make use of it (ie, putting 92 octane gas in a low compression engine like many American-made engines isn't going to help anything, while putting 87 octane in a high compression Porsche engine is going to give you poor performance and mileage). If it's bad gas you're worried about, the most common problem is too much water in the gasoline. You can solve this problem with an alcohol additive to "dry" the gas. Other problems like too much sulfur (I believe that was the problem recently with some gas down in Florida, among other places) don't have an easy remedy, and all you can do is stop driving, have the car towed, and empty the tank. Run a few tanks of good gas through the engine and it'll be fine.

As others have already stated in this article, there are many other factors to consider. Low tire pressure, dirty air filter, oil, oil filter, bad alignment, too much weight (of the driver, passengers, and any cargo), etc will all have an effect on your mileage. Also, most cars will get their best mileage at low RPMs. If you can cruise at 2000RPM, you're going to get much better mileage than cruising at 5000RPM (just be careful -- you're going to be in a high gear to cruise at such a low RPM, and trying to accelerate in that gear could cause you to lug your engine. This is more important in high-revving, low-torque engines than it is in low-revving, high-torque engines).

Links:

• HowStuffWorks on gasoline
• Gasoline FAQ

...my bike get's about 3 meals/day, though after a period of getting 2/meals per day effeciency seems to improve. You laugh, but I can spin at 20 MPH and sprint well over 30. Check out how many calories are in a gallon of gas and tell me how efficient you feel your Pirus is now....

The problem is the ISPs want to own your IP address and they use the shortage in IPV4 to retain control.

Why does this seem like the charge of the tinfoil hat brigade?

What a nefarious plot! The techies who route Internet data want to be able to assign the numbers they need to route it!

Saying that the ISPs want to own my IP address is like saying the phone company wants to own my port number on their switches. Duh! An IP address isn't a phone number, or anything close to it. This is a very bad analogy, but a domain name is more like a phone number. A phone number can be associated with any one of many different actual phone connections. Likewise, a domain name can be associated with any one of many different IP addresses. The whole point of the DNS system is to have portable addresses (domain names) which are independant of IP addresses. What this lazy, litigious oxygen-thief wants to do is basically break the entire routing system, and he's got some damnfool judge who thinks the Internet is something to catch Interfish with to agree with him. Letting an ignorant fool like that make decisions about how the Internet should be managed is like having some random net user making legal rulings. If you don't know wtf the situation involves, as it is clear that this judge didn't, then find someone who does.

Someone needs to whack the bloody fool of a judge with a clue-by-four. Maybe with a copy of The Internet for Dummies. For the love of Kibo, at least send him a link to How Stuff Works.

In case anyone is interested, here is the fireworks page from How Stuff Works.

I think you're right to pick out batteries as an important developing technology. Well, I'd generalize it to power. If power consumption can be reduced enough there are many alternative sources of power.

Suggestion:

1) Read about something.
2) Understand something.
3) Post about something.

Ditto to the moderators who modded this informationally devoid post as informative.

Do you honestly think the designer and test pilot of the first successful private space launch would expect ailerons and elevators to work in a near vacuum? You do know they used computers and sophisticated computational fluid dynamics (CFD) to analyze SS1's aerodynamics throughout the entire range of flight, from freefall after initial separation at 120 knots, through mach 3, and into space, right? This isn't a 7th grade class science project. Maybe you should email to tell them which way gravity pulls, too.

You get my Mr. Obvious Slashdot Award of the week.

If you'd actually like to learn about SS1:
http://www.howstuffworks.com/spaceshipone.htm
http://www.scaled.com/

All about decaffeination.

Well, with any government project, kickbacks are always a problem, but in this case I'd be more concerned with recoil. :)

Microgravity:An environment in which there is very little net gravitational force, as of a free-falling object, an orbit, or interstellar space. (emphasis mine)

Weightlessness: Not experiencing the effects of gravity.

Gravity is still very significant at those altitudes.

Therefore, you're not weightless.

because he was coasting freely along with it.

In other words, he was in freefall, and experiencing 'microgravity.'

Gravity is still very significant at those altitudes.

And you're right; in orbit, you're still very much affected by gravity; an 'orbit' is simply 'falling towards, but keep missing' sort of thing. You're not weightless, you're in freefall, and therefore experiencing 'microgravity.'

From a howstuffworks.com article:

Weightlessness is more correctly termed microgravity. You are not actually weightless, because the Earth's gravity is holding you and everything in the shuttle in orbit. You are actually in a state of free-fall, much like jumping from an airplane except that you are moving so fast horizontally (5 miles per second or 8 kilometers per second) that, as you fall, you never touch the ground because the Earth curves away from you.

Here's all the dirt on HDTV. Read and enjoy :)

How Stuff Works: How Terraforming Mars Will Work

Used in this way, hydrogen peroxide is a monopropellant.