Explanation of the Day

• ndmmxiaomayi

  12 Feb 06, 00:35

  How do houseflies manage to land on the ceiling upside down?
  
  Think about this one...When the fly is heading for the ceiling, it's flying right side up. When it lands on the ceiling it is upside down. At some point along the way it has to flip over. But when? And Where? And How?
  
  Scientists dispelled the prevalent theory, that the fly performed a fighter pilot-like barrel roll just prior to landing, by capturing this momentous event on film.
  
  Freeze frames, from the high-speed cameras scientists used, proved that flies do not flip, but flop, as they land upon the ceiling. Prior to impact, the fly extends its forward legs over its head, makes contact, and uses the momentum it has gathered in flight to hoist the remainder of its body to the ceiling. Thus, the fly proves to be more of an acrobat, than of a fighter pilot practicing his maneuvers.
  
  Once the fly reunites all six feet on the ceiling, it keeps things dizzingly exciting, by gracefully tiptoing across the ceiling, securing itself by using sticky pads found under the two claws attached to each of its feet. It is because of these sticky pads and the hairs on the legs that the fly is such a carrier of disease germs.
• ndmmxiaomayi

  12 Feb 06, 21:17

  Who invented the zipper?
  
  Why do most Zippers have the letters YKK on them?
  
  Whitcomb L. Judson invented the zipper and YKK is the Japanese company that makes them.
  
  Whitcomb L. Judson was a lover of gadgets and machines and the idea for his "clasp locker" came from when a friend had a stiff back from trying to fasten his shoes. Judson's clasp locker was used mostly on mailbags, tobacco pouches and shoes. However, his design, like most first inventions needed to be fine-tuned.
  
  A more practical version came on the scene in 1913 when a Swedish-born engineer, Gideon Sundback revised Judson's idea and made his with metal teeth instead of a hook and eye design. In 1917, Sundback patented his "separable fastener."
  
  The name changed again when the B. F. Goodrich Co. used it in rubber boots, galoshes, and called it the "zipper" because the boots could be fastened with one hand.
  
  The 1940s brought about research in Europe of the coil zipper design. The first design was of interlocking brass coils. However, since they could be permanently bent out of shape, making the zipper stop functioning, it was rather bad for business and wasn't too practical. The new design was improved after the discovery of stronger, more flexible synthetics. Coil zippers eventually hit the market in the early 1960s.
  
  In 1934, Yoshida Kogyo Kabushililaisha was founded. Sixty years later they changed their name to YKK Co. The privately owned firm, headquartered in Japan, now is made up of 80 companies at 206 facilities in 52 countries. Wow! you say? but of course, the demand for zippers is great. YKK makes everything from the dyed fabric around the zipper to the brass used to make the actual device.
  
  Did you know?
  
  

  
  [*] In the 1930s a sales campaign ran for children's clothing that used the new zippers. The device was praised for promoting self-reliance in young children. "Mommy look! One zip and I'm all dressed!"
  [*] In 1937 in the Battle of the Fly it was zipper versus button. French fashion designers went wild for the new invention for men's trousers.
• ndmmxiaomayi

  13 Feb 06, 21:04

  How do fingernails grow?
  
  Fingernails and toenails grow from a point near the roots below the skin, at the base of the nail where the nail is very thin. White in color, and half-moon in shape, this semi-circle is appropriately named the "lunula," and comprises a group of cells that manufacture keratin, a dead, hoof-like protein. The keratin like protein produced, gathers and merges with the nail plate, the dead armor that protects the soft and tender nail bed underneath, and pushes the entire nail up and out. Though the fingernails and toenails grow an average of two inches per year, their growth slows with age, and the average adult's fingernails grow only one inch over the course of eight months.
  
  The base of the fingernails and toenails, as well as some of the nail along both sides of the nail, are embedded into the skin. Unlike other skin, this skin contains elastic fibers that connect it to the fingernail or toenail, and hold it firmly in place. The cuticle, a rim of skin over the lunula, protects it from bacterial infection, serves as a shock absorber, and shields the nail from any sudden impacts.
  
  Though many consider dressing the fingernails up to go out a statement of beauty, or one of vanity, they serve those in the medical field as a diagnostic tool. Normally, the lunula, or half-moon, is white in color, indicating proper nutrition and good overall health. Blue lunula raise red flags that circulatory problems to the fingers may exist. Nails that are hard, brittle, and tend to split easily, may also be clues to poor circulation, infection, or disturbances of the glandular and nutritional systems.
  
  Further nails that curl sharply around the finger point to coronary, liver, or lung diseases. Nails that are sunken in appearance often indicate anemia, a condition where an insufficient amount of oxygen is carried by the blood.
• ndmmxiaomayi

  15 Feb 06, 22:40

  Why do Wintergreen Life Savers make little blue sparks when you crunch them with your teeth?
  
  What we have here is something called triboluminescence or TL. Simply put, triboluminescence is light resulting from crushing or tearing.
  
  Provided by methyl salicylate (oil of wintergreen), when the sugar crystals in the Life Savers get crushed, electrons break loose and scatter all over creation. The electrons begin to get lonesome for the sugar crystals they broke free from, and decide to return. Problem is that nitrogen molecules took their place and the electrons crash into the nitrogen - causing little blue sparks.
• ndmmxiaomayi

  15 Feb 06, 22:42

  Why do body joints make popping sounds?
  
  Do a deep knee bend, and it's very likely you'll hear popping sounds coming from your knee joints. There are also popping sounds when you "crack your knuckles."
  
  What causes the popping sounds? Actually, two separate and distinct sources are responsible for the familiar popping sounds our joints emit.
  
  The sound heard when our knuckles crack, results when a finger joint is extended almost to the end of its range. The joint, surrounded by a lubricating fluid, is encased in a capsule. At times, we intentionally, or unintentionally, extend the joint so far that the gas dissolved in the fluid spontaneously separates from the solution, forming a small bubble, and making a cracking sound. Not until the fluid reabsorbs the gas can the sound be reproduced. Whether or not there is truth to the old wives tale, that cracking ones knuckles enlarges them, remains open to debate.
  
  On the other hand, the sound produced when we do deep-knee bends, is a snapping sound, produced when our tendons, which are merely the fibers that connect muscles and bones, elastically snap into new positions as our joints move under stress. Because the tendons shift back and forth with the movement of the joint, there is no waiting time before this snapping sound can be reproduced.
• ndmmxiaomayi

  18 Feb 06, 13:59

  What makes popping corn pop?
  
  Corn is a generic term to describe the fruit (grain) of cereal plants in particular. In Britain corn generally refers to wheat. However, in the US, the word corn refers to maize. Popping corn is just one of the many varieties of maize grown commercially.
  
  The bulk of tissue within a grain of corn is called the endosperm. Endosperm is specialized storage tissue providing nutrients for the embryo when the seed germinates. It is also a source of carbohydrates for humans. In popcorn, the outer part of the endosperm is hard but the center is soft. When the corn is heated, the water in the central part turns to steam causing the seed to burst (the pop that you hear) and turn inside out.
• ndmmxiaomayi

  18 Feb 06, 14:02

  What is a booger made of?
  
  Boogers are mucus (myoo-kuss). Mucus is the thin, slippery material that is found inside your nose. Many people call mucus snot. Your nose makes nearly a cupful of snot every day. Snot is produced by the mucous membranes in the nose, which it moistens and protects.
  
  When you inhale air through your nose, it contains lots of tiny particles, like dust, dirt, germs, and pollen. If these particles made it all the way to the lungs, the lungs could get damaged and it would be difficult to breathe. Snot works by trapping the particles and keeping them in the nose.
  
  After these particles get stuck inside the nose, the mucus surrounds them along with some of the tiny hairs inside the nose called cilia. The mucus dries around the particles. When the particles and dried-out mucus clump together, you're left with a booger!
  
  Boogers can be squishy and slimy or tough and crumbly. In fact, boogers are a sign that your nose is working properly.