Here's a fun science experiment: finely powder some rust and then blow it over the magstripe on your credit card and you can see the zeroes and ones encoded on it by the stripes where the magnetic forces attract the ferrous particles. For a bonus, Anaglyph tried this out on a woo-woo product called a Shoo!Tag, which is supposed to use "a three dimensional or trivector signature imprinted onto the magnetic field of a three field magnetic memory card to create a protective barrier from pests." No evidence of a "trivector signature" was in found.
Another Science Experiment
Amazing! The fine particles clearly delineate the data on the card! What we're seeing here tells us lots about how a credit card works. First of all, you will notice that Gilbert's card has three horizontal magnetic bands. This is the standard for all swipe cards. In most cases, information is recorded on one, or sometimes two of these bands. The two outside bands are called high density tracks and contain data at 210 bits per inch. If you know anything about computers, you will realise that the term 'high density' here is relative: 210 bits per inch, by modern data standards, is pretty damn lousy. To give you some idea, one of these tracks can carry about 79 x 6bit alphanumeric characters. Your credit card would typically have, on track 1, your name, your card number and an expiry date. That's it. Not much.
That point of light between Saturn’s rings is Earth, captured by NASA’s Cassini spacecraft on April 12. More about the image here at NASA JPL. It reminds me of the last photo taken by the Voyager I spacecraft before engineers shut off its imaging systems. Carl Sagan had persuaded NASA to turn Voyager I’s cameras […]
As AI improves, the mystery of consciousness interests more programmers and physicists.
Most of us need a computer interface implanted in our brains like we need a hole in our head. That said, there are benefits to bridging the gap between mind and machine. Joel Murphy is the founder of OpenBCI, an inexpensive, and non-invasive, brain-computer interface (BCI) platform. People have used OpenBCI to control robots, compose […]
Even the most expensive pair of hi-fi headphones can’t match the feeling of bass rumbling through your body at a live show. That’s why music aficionados designed The Basslet, an accessory that reproduces that sensation from your wrist. Does it make your whole body shake with deep subs? Not really, because that would be terrifying, but […]
They probably just sleep a lot. But still, you can remotely keep an eye on them when you’re at work and missing them deeply with this HD monitor from Kodak.If you have a new puppy that destroys everything in sight, or you just want to be a little more security-conscious, this WiFi camera is a […]
Thinking of a business idea is the easy part. Doesn’t even have to be a “good” idea, you can still get people to throw money at a non-existent venture, but to do that you need to at least have something even resembling a viable business plan. Why doesn’t anyone do it then? Because building that semi-viable […]