Knowledge Firm

Captcha stands for: Completely Automated Public Turing test to tell Computers and Humans Apart. It is used by many websites to make it harder for automated bots to download information from them. These bots are usually made by hackers and so many websites use this technology to counter them. it's not always successful because the bots are getting more sophisticated.

Have you seen a floppy? Floppies were a type of disk storage used earlier before the current system of storage came into existence. Floppy disk drives were named with the letters A and B. When hard disk drives became standard in most computers, they were logically labeled 'C' since the first two letters were already used for these floppy drives. Though floppy disk drives are no longer widely used, hard disks are still labeled from 'C' onwards.

Dry ice is frozen carbon dioxide. A block of dry ice has a surface temperature of -109.3 degrees Fahrenheit (-78.5 degrees C). Dry ice also has the very nice feature of sublimation -as it breaks down, it turns directly into carbon dioxide gas rather than a liquid.

The Spidercam is a system that enables film and television cameras to move both vertically and horizontally over a predetermined area, typically the playing field of a sporting event such as a cricket pitch, football field, or a tennis court. The name Spidercam is a trademark.

Dental X-rays (Radiographs) are images of your teeth that your dentist uses to evaluate your oral health. These X-rays are used with low levels of radiation to capture images of the interior of your teeth and gums. This can help your dentist to identify problems, like cavities, tooth decay, and impacted teeth.

A Baby does not need to breathe in the uterus. Everything that it needs for its growth is provided to it by its supply line: the umbilical cord. This cord connects the blood circulation of a child with the mother. The fetus gets nutrition and oxygen through the umbilical cord. The waste products of the fetus are thrown out into the blood circulation of the mother and are excreted by the mother. After the birth of the baby, the umbilical cord is no longer required and cut off.

Dry cleaning is any cleaning process for clothing and textiles using a chemical solvent other than water. It is used to clean fabrics that degrade in water, and delicate fabrics that cannot withstand the rough and tumble of a washing machine and clothes dryer. Dry cleaners use a variety of solvents to clean fabric. Early solvents included gasoline, kerosene, benzene, turpentine, and petroleum, which were very flammable and dangerous, according to the State Coalition for Remediation of Drycleaners (SCRD), a group whose members share information about cleanup programs. The 1930s saw the development of synthetic, nonflammable solvents — such as perchloroethylene (also known as perc or PCE) and decamethylcyclopentasiloxane (also known as GreenEarth) — which are still used today.  Detergents are typically added to the solvents to aid in the removal of soils, according to an SCRD report titled "Chemicals Used in Drycleaning Operations." Detergents aid d...

Underneath the frozen upper layer, the water remains in its liquid form and does not freeze. Also, oxygen is trapped beneath the layer of ice. As a result, fish and other aquatic animals find it possible to live comfortably in the frozen lakes and ponds.

When the bowler is rubbing one side of the ball he is actually polishing or smoothening the surface of the ball. Another half of the ball remains as it is or rougher. When the baller throws the ball at high-velocity low pressure is created near a smooth surface and a high-pressure area is created on the rougher side. This pressure differential SWINGS ball in the air.

For aerodynamic purposes. A smooth, solid ball won't fly nearly as straight or far as a golf ball with dimples. This is due to the thin layer of turbulent air the dimples create on a golf ball in flight. Small hollows that are present on the surface of a golf ball are called 'dimples'. The dimples on a golf ball "create a thin turbulent boundary layer of air that clings to the ball surface. This allows the smooth flow of air.

The trapped steam increases the atmospheric pressure inside the cooker by 15 pounds per square inch (psi), or 15 pounds above-normal sea-level pressure. At that pressure, the boiling point of water is increased from 212°F to 250°F. This higher temperature is what cooks food faster.

The Pentagon serves as the headquarters of the United States Department of Defense. As one of the world's largest office buildings, it has a floor space of 3,705,793 square feet or three times that of the Empire State Building in New York. The Pentagon houses a daily working population of approximately 24,000 employees, both military and civilian.   The pentagon was designed in such a way that no part of the building is more than a 10-minute walk from any other point in the building. It was purposely built short. The Pentagon was built short due to two reasons: Steel was in short supply due to the Second World War, and they wanted to conserve steel. The designers apparently wanted to conserve the “view” of The Capitol across the Potomac and building it higher would ruin the view.

The official name of the UK is the "United Kingdom of Great Britain and Northern Ireland." The name refers to the union of what were once four separate nations: England, Scotland, Wales, and Ireland (though most of Ireland is now independent). The United Kingdom is made up of: England - The capital is London.

The reason dates back to the time of manual typewriters. When first invented, they had keys arranged in alphabetical order, but people typed so fast that the mechanical character arms got tangled up. So the keys were randomly positioned to actually slow down typing and prevent key jams. In 1968, the first typewriter was designed with an alphabetical order similar to the arrangement of piano keys. But because all the commonly used letters were so close together, the keys kept getting jammed. Christopher Latham Sholes then invented the 'QWERTY' keyboard with the purpose of spreading apart popular keys to avoid mechanical issues. However, researchers have theories that it dates back to times when morse code was used and the alphabetical arrangement confused telegraph operators when transcribing messages.

When you cut an onion, it releases a gas called, ready for this, Propanethiol S-oxide. When mixed with certain enzymes in the onion, it creates a sulfur gas. These gases then get to your eyes and create a mild acid that irritates the eyes.

The beer bottle is a bottle made to contain beer, usually made of glass, and comes in various sizes, shapes, and colors (usually brown or green). Dark amber or brown glass greatly reduces the presence of UV light, a contributing factor of beer spoilage. However, lighter-colored bottles are often used for marketing reasons.

The Audi logo with its 4 rings identifies Germany's oldest-established automaker. It symbolizes the association in 1932 of 4 previously independent motor-car manufacturers: Audi, DKW, Wanderer, and Horch. These companies initiate the roots of that is today AUDI.

The components of making a disposable diaper are the following: waterproof wood pulp, and synthetic polyacrylate (Cloth Diapering). In disposable diapers, polyethylene plastic is used and the raw material for this is the oil; it takes 1 cup of crude oil to make the plastic for one disposable diaper.

It is a passive electrical device that helps to isolate the laptop from electromagnetic noise, either from waves picked up by the wire (which acts like an unintentional antenna) or from existing noise in the upstream AC line or AC-DC converter. Although it probably is not necessary for everyday usage, it allows the laptop to pass FCC tests for being able to accept a certain amount of environmental EM noise.

When touched, this sensitive leaf reacts to the stimulus as there is higher pressure at that point and the water in the vacuoles of the cells of the leaf loses water to the adjacent cell. All the water escapes the leaf (via the pulvinus) which then becomes flaccid.