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May 22, 2012

David S. Cloud and Kathleen Hennessey: Obama changes mind on Pakistan invite to NATO summit --- and then gets dissed by country's president
Warren Richey: Can US group challenge overseas surveillance act? Supreme Court to decide
Thomas M. Anderson: Walking Away From a Mortgage
Environmental Nutrition editors: The lowdown on a low-acid diet
The Kosher Gourmet by Megan Gordon: Enjoy a celebration of the most rich and layered flavors: Black bean, sweet potato and quinoa chili
May 21, 2012
Mark Clayton: Cybersecurity: How US utilities passed up chance to protect their networks
Howard LaFranchi: NATO summit: Who will foot the bill for long-term Afghanistan security?
Chris Farrell : Earn Dividends in Emerging Markets with This WisdomTree ETF
James K. Glassman: 5 Stock Picks Among Online Retailers
Stephen Whiteside, Ph.D. : Mayo Clinic Medical Edge: Social anxiety disorder --- or just shy?
Guy Jackson : Victim's father regrets death of Lockerbie bomber
The Kosher Gourmet by Mario Batali: Famed chef's veal shoulder farsumagru: A festive meat course for late spring
May 18, 2012
Rabbi Berel Wein: Striving: The People of the Book's Book for (All of) the People
Caroline B. Glick: Embracing dangerous delusions and not our friends
Steven Goldberg: 5 Great Stock Picks and the Exchange-Traded Fund that Owns Them
Janet Bodnar: How to Teach Kids to Handle Credit Cards
Mary Pickett, M.D.: Ask the Harvard Experts: Don't be forced into gluten-free lifestyle based merely on a doctor's false-positive test
The Kosher Gourmet by Carolyn Malcoun: DIY healthy lunchbox treats: HOMEMADE FRUIT BARS for kids and brown-bagging adults alike
May 17, 2012
Warren Richey: Teacher fired for being unwed and pregnant can sue religious school, court rules
Josh Mitnick: Netanyahu's 'centrist' coalition is already proving it's anything but
Steven Goldberg: Earn Dividends in Emerging Markets with This WisdomTree ETF
Mary Beth Franklin: Retirement Savings Tips for New Grads
Amina Khan: Research links coffee to lower death rates
Chelsea Sheasley: Social media: Is it too feminine?
The Kosher Gourmet by Faith Duran : Cheesy Potato Breakfast Casserole with Cheddar and Sun-Dried Tomatoes
May 16, 2012
Jackson Holahan: The Aleppo Codex
Jonathan Tobin : Iran Declares Victory in Nuclear Talks
Anne Kates Smith: 7 Stocks That Let You Sleep Tight
Carmen Terzic, M.D., Ph.D. : Mayo Clinic Medical Edge: A variety of exercises can help improve balance
Melissa Healy: National strategy on Alzheimer's disease aims to halt it by 2025
The Kosher Gourmet by Joyce White : GOODNESS GRACIOUS: GREENS! 4 winning recipes that are no longer just for down-home folks (Includes expert tips & techniques)
May 15, 2012
Dennis Prager: God and Man at (and for) Liberty
Kristen Chick: Obama administration resumes arms sales to Bahrain despite serious unresolved human rights issues. Activists feel abandoned
Pat Mertz Esswein: Homes are now affordable again and mortgage rates are low. What you need to know before you buy
Kathy Kristof: Our Practical Investor Fights Inflation with These 6 Investments
Sue Hubbard, M.D.: The Kid's Doctor: Lactose intolerant young child? Check again
Environmental Nutrition Editors: Get the facts on palm sugar sweetening
The Kosher Gourmet by Kathy Hunt: Spread a Little Excitement with EXOTIC CONDIMENTS (4 RECIPES)
May 14, 2012
Richard Simon: Purple Hearts for domestic terror victims?
Nando Pelusi, Ph.D.: The privacy paradox: Surrounded by strangers, we risk isolation, anxiety
Chris Farrell: Investing Lessons from the Great Recession
Lisa Gerstner: How to Protect Your Identity, Finances If You Lose Your Phone
Harvard Health Letters: Heart disease and dementia
Tiffany O'Callaghan: New hormone mimics effects of exercise without the sweat
The Kosher Gourmet by Megan Gordon: MANGO COCONUT OAT MORNING MUFFINS are a bright but hearty delight
May 11, 2012
Rabbi B. Shafier: Why happiness will always be elusive
Charles Krauthammer: Echoes of '67: Israel unites
Howard LaFranchi: With G8 snub, US-Putin 'reset' off to stumbling start
Jeremy J. Siegel: Investors, Relax About Rising Interest Rates
Jessica L. Anderson: Get the Best Deal on a Used Car
Jett Stone: Forget face-lifts and fake knees. Scientists have seen the fountain of youth --- and it's broccoli
The Kosher Gourmet by Chef Mario Batali: The famed chef's vegetable dish that tastes true to the season: FAVAS AND SUGAR SNAP PEAS WITH POTATOES AND TARRAGON
May 10, 2012
Clifford D. May: The Real Palestinian Refugee Problem
Sergei L. Loiko: Putin sends warning to U.S., NATO in Victory Day speech at Red Square
Mary Rourke: How being a 'mentch' got Vidal Sasoon his start and fighting in Israel's War of Independence provided him with confidence and a strong sense of his own identity
Harvard Health Letters: Palliative care: Underused therapy yields surprising benefits
Jeff Bertolucci: Get Home Phone Service for Less Than $10 a Month
Rachel L. Sheedy and Susan B. Garland : Make the Right Moves to Boost Benefits
The Kosher Gourmet by Betty Rosbottom: Gleaming with its golden, crimson, and snowy white hues, this silken smooth and creamy STRAWBERRY ORANGE TRIFLE looks impressive, but is easy to prepare
May 9, 2012
John Rosemond: Parents, stop destroying the American male
Valerie J. Nelson: Maurice Sendak, author of 'Where the Wild Things Are,' dies at 83
Bob Frick: Angst Over Annuities
Sharon Palmer, R.D. How you can reduce your risk -- or delay -- chronic diseases associated with aging
Howard LeWine, M.D.: Ask the Harvard Experts: Why did my blood pressure suddenly shoot up?
Lisa Gerstner: Lower the Rate on All Your Loans
The Kosher Gourmet by Emily Ho : Springtime soba with miso sauce offers a coloful mix of fresh textures and flavors
May 8, 2012
Edmund Sanders: Netanyahu suddenly cancels new elections, forms unity government
Frank J. Gaffney Jr.: Farewell to European superstate
Anne Kates Smith: 4 Stocks That Mimic Buffett and Berkshire Hathaway
Gaia Vince and Clare Wilson The Rise of Miniature Medical Robots: Fantasy Fast Becoming Reality
Paul Takahashi, M.D.: Mayo Clinic Medical Edge: Never suffer night leg cramps
Jessica L. Anderson: Extended-Warranty Warning
The Kosher Gourmet by Diane Rossen Worthington: Celebrate National Chocolate Chip Day with the Best Cookie Ever (Includes techniques)
May 7, 2012
Mark Clayton: Homeland Security warns major cyber attack aimed at gas pipeline industry underway
Angus Roxburgh: Putin Decoded: World view of a Russian feeling dissed
Kimberly Lankford: Navigate a Course for Long-Term Care
Kevin McCormally How to Adjust Your Tax Withholding
Celeste Robb-Nicholson, M.D.: Harvard Health Letters: How do you treat a Baker's cyst?
Joanne Capano: Healthy Snacks for Children: The Choices May Surprise You
The Kosher Gourmet by Penelope Wall: Classic Creamy Spinach Dip with a Fraction of the Calories and Fat
May 4, 2012
Rabbi Nathan Lopes Cardozo: Holy 'trivialities'
Jonathan Tobin: Bibi v. Barak will be no contest this time around
Steven Goldberg: Blue Chip Stocks On Sale Worldwide
Art Pine Slow Productivity Growth a Blessing --- For Now
Sue Hubbard, M.D. : The Kid's Doctor: Are Kids Too Wired?
Kerri-Ann Jennings, M.S., R.D: Foods that are good for your smile
Amy Paturel, M.S., M.P.H.: Eating Well: Foods that are good for your smile
The Kosher Gourmet by Betty Rosbottom: Strawberry rhubarb parfaits are elegant yet simple to assemble
May 3, 2012
Michael Freund: Who's Afraid of the Messiah?
Clifford D. May: The Foggiest War
Susan B. Garland: Insurance to Cover Old Old Age
Steven Goldberg 6 Reasons to Bet on a Big Bull Market
Harvard Health Letters: Treating prostate cancer --- no rush to judgment
Larry Gordon: Harvard, MIT partner to offer free online courses
Naomi Nix : Man gets free trip to Chicago after postcard sent by mother in 1957 finally reaches him
The Kosher Gourmet by Diane Rossen Worthington: Intensely Italian vegetable frittata is a seriously simple standby


Jewish World Review

How airbags work

By Marshall Brain

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http://www.JewishWorldReview.com | (MCT) Imagine for a moment that you are driving your car. It's a beautiful day, and you are driving down the freeway at 60 mph. The windows are down; the radio is playing. You have not a care in the world.


The funny thing is that when you are sitting in that position, you are positioned right in front of an explosion that is waiting to happen. There is a computer in your car dedicated to that explosion - its single goal in life is to set that explosion off. And the computer is listening to a tiny sensor that in many cars is no bigger than a pea. When that sensor decides it is time for the explosion to happen, the computer will hear its tiny signal. In less than a millisecond the explosion will start. When the explosion happens, it is powerful enough to kill people, but for most people it is not deadly. Instead, it saves their life.


Welcome to the world of airbags. An airbag is an explosion designed to protect rather than to destroy.


The reason why your airbag is poised and ready to explode out of your steering wheel is because an accident can happen at any moment. For example, a car driving the other direction on the freeway could suddenly veer across the median and run into you head-on.


At the moment of a head-on collision, your airbag has about 5 hundredths of a second to react. During that time, your body is going to decelerate from 60 mph to 0 mph. The goal of the airbag is to help that deceleration happen as gently as possible.


The first thing that detects the crash is an accelerometer. An accelerometer is simply a device that can sense when something is rapidly accelerating or decelerating. Many cars use a tiny micro-machine etched out of silicon to detect the crash. But an accelerometer could be as simple as a steel ball attached to a magnet at one end of a small tube. During a crash, the ball breaks free from the magnet and hits two metal contacts to complete a circuit. The airbag control computer gets a signal from the accelerometer. Most cars have four or five accelerometers, and the airbag computer wants more than one of them to send a signal to be sure it is not a false alarm. Once the computer is satisfied that this is the real deal, it starts the fireworks.


What happens next is rather amazing. Inside your steering wheel is a bag made out of a fabric like nylon. There is also a metal canister called an inflator that contains sodium azide. Sodium azide is a highly reactive chemical that is very much like the fuel in a solid rocket engine. The signal from the computer fires an igniter, which lights the sodium azide. The sodim azide reacts incredibly quickly and it produces a huge cloud of hot nitrogen exhaust gas. That gas goes straight into the nylon bag. The bag inflates in a few milliseconds, with the front of the bag bursting out of the center of the steering wheel at 200 mph. This 200 mph piece of fabric is heading straight for your face.


The reason why it is heading for your face is because, if you think about it, your head is the most important thing to protect in this collision. Your torso is held in place by the seatbelt, but your head, attached to your spindly little neck, weighs as much as a bowling ball. This bowling ball contains your brain. Your brain is pretty fragile and it is still moving forward at 60 mph. The idea behind an airbag is to slam the piece of nylon, backed by a jet of nitrogen gas, into your head at 200 mph. That way, your head slows down to zero MPH as gently as possible. The airbag also takes a big load off your neck. Without an airbag, your neck has to take all the stress of bringing your bowling ball head to a stop.


So think about this the next time you are driving down the road. Sitting in front of you is your own personal explosion, connected to its own explosion-control computer. Around your car there are a number of hidden collision-sensing accelerometers. All of this equipment is sitting there quietly, waiting to bring your bowling ball head to a stop in 5 hundredths of a second, should the need ever arise.

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Previously:


How the U.S. income tax works
How gum works
How caffeine works
How Daylight Saving Time works
How a cruise missile works
How snow making works

© 2007, How Stuff Works Inc. Distributed by McClatchy-Tribune Information Services.

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