Golf Balls -- The Science Behind The Dimples
The dynamics behind the flight of the golf ball offers a fascinating insight into the physical interworkings of air pressure, turbulence, and aerodynamics.
When golf was first played in Scotland, most players played using clumsy golf apparatus, with the first golf clubs and golf balls made of wood.
In 1618 the "Featherie" was introduced. It was a golf ball made of feather. This feather golf ball was handcrafted from goose feathers tightly pressed into a horse or cowhide sphere while still wet. After drying, the leather shrank and the feathers expanded, creating a hardened golf ball.
As this type of golf ball was specially handcrafted, it was usually more expensive than golf clubs, so that only a few privileged people could afford to play golf back then.
After the Featherie golf ball came the Guttie golf ball. This type of golf ball was made from the rubber-like sap of the Gutta tree found in the tropics, and was shaped into a sphere when hot and eventually into a golf ball. As it was made of rubber, the Guttie golf ball could be cheaply produced and easily repaired by reheating and reshaping.
Comparing the two types of golf balls, the Featherie golf ball was said to travel farther than the Guttie golf ball because the Guttie golf ball's smooth surface prevented it from covering more distance.
With this discovery, the developers of golf balls came up with the "dimpled" golf balls that are so predominant in modern golf nowadays.
The dimples on the golf balls help reduce the aerodynamic drag. Aerodynamic drag normally affects smooth golf balls and slows them down, because when they sail through the air, they leave a pocket of low-pressure air in its stir thus creating a drag.
By applying dimples to the golf ball surface, the pressure differential goes down and the drag force is reduced. These dimples create turbulence in the air surrounding the golf ball, which, in turn, forces the air to clasp the golf ball more closely. By doing so, the air trails the warp created by the golf ball towards the back instead of flowing past it. This results in a smaller wake and lesser drag.
Dimples were first added onto golf ball surfaces back during the gutta percha phase. Coburn Haskell introduced the one-piece rubber cored golf ball encased in a gutta percha sphere. Then in 1905 William Taylor applied the dimple pattern to a Haskell golf ball, thus giving rise to the modern golf ball as we know it today.
After its beginning, dimpled golf balls were officially used in every golf tournament. In 1921, the golf ball took its current form with standard size and weight. Nowadays there is a wide range of golf balls to fit every style, game and condition, with some golf balls offering control, and other golf balls offering distance.
Though a common sight nowadays, the dimpled golf ball is not just a mere element of the sports arena; it is a showcase of physics at work.
Online Poker History - The Story Behind The Sensational Hit
Online poker is defined as the type of the poker game played in the internet by either one person or a number of participants. The ease of accessibility is what has made on-line poker very popular because of its appealing nature that has seen many people turn to it as a major form of entertainment. It is estimated that in 2003 alone almost USD$ 35 million was collected in monthly revenue from on-line poker alone.
The game of poker has been going for many years, but the history of online poker - along with most other online games - is relatively short. Yet despite the relatively short length of the history of the game, it is an extremely rapid developing part of the entire online gambling industry which is not showing any signs of slowing down. While it is very popular in America, Europe is fast catching up too.
The history of online poker begins with the history of poker in general. The game of poker has been around for thousands of years with origins all over the world, from China to France to Persia and Spain. However, it wasn't until 1834 that the game of Poker with the name of "Poker" was officially recorded. Jonathan H. Green wrote about "the cheating game" which was played on Mississippi riverboats. This game was played with only twenty cards, but evolved into modern day poker.
Online poker only dates back 9 years, to 1998 which was when the first games came on line. But the real milestone for the history of poker was 2002. A year later when the World Poker Tour was launched on America's travel channel in March, poker really hit off. This was also true for when the World Series of Poker (WSOP) had its largest turn out over.
These events and others certainly contributed to the developing growth of the history of poker as more and more individuals found out about how fun the game was to play on line, and indeed, how lucrative it could be, especially when playing online poker tournaments. 2004 and 2005 saw a huge influx of additional online poker rooms and sites, many of which appealed to the masses, even the non-poker playing ones who started to show an interest in this new and exciting online game.
Poker is a game that is coordinated by gambling laws and regulations and is mainly played in casinos and card rooms. However, it has recently become available for play in online poker rooms. The introduction of poker to the Online has increased the popularity of the game a huge amount, but it didn't start out so simply.
The history of online poker began in 1998, when the first online poker room was opened. Planetpoker. com was the first website in the history of online poker and as the first it had many obstacles to overcome. One of the main problems was trust-after all they had to build peoples' trust in order to get them to play with real money on their site. They also had to work out software that would be user friendly and realistic. However, once they worked out these problems it was a smooth ride.
Probably one of the reasons the history of online poker developed so well was because of how enthusiastic poker professionals have been since the game's inception on line. Such big names as Chris "Jesus" Ferguson, Howard Lederer, Phil Ivey, Erik Seidel, John Juanda, Phil Gordon, Andy Bloch, and Erick Lindgren are included in this list.
The history is now definitely well on the map, especially financially as the industry in America has reached over $2 billion. There are so many poker rooms today on line that pretty much at any time, 24/7, one is able to find a poker game of their choice. Whether you love 3 card poker, video poker, Texas Hold'em Poker, 7 card stud poker, 5 card draw poker, Omaha Hi-Lo poker, to name but a few, on line players will probably be able to find a game to satisfy and appeal.
Many online poker sites offer now offer numerous features that attract and appeal to new players. This new features are what are making raves in the world series of poker because the world of poker has now wakened to the realization that even on-line poker participants can also have a shot at the big game.
One similar feature offered by the online poker sites is the tournament referred to as "satellite". This feature allows participants to gain actual access to real live poker tournaments. In a similar tournament Chris Moneymaker emerged the victor and was able to participate in the World Series of Poker in 2003. his victory shocked the whole world.
Recent figures have in fact projected that the revenue generated by on-line poker could reach as high as US$ 100 million target in 2005, and that online participants are estimated to reach 100,000 people.
what do you place behind a dart board?
What do I out behind a dart board to protect the wall from bad throws? Do I hang the dartboard over the protective layer?
Putting up a dart board - what material to put behind the board?
I'm putting up a dart board and am wondering what kind of material you guys recommend I put behind it (so I won't get holes in the wall) 
At the same time, I'd like it to look pretty classy. Thanks!