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A blowdryer or hair dryer is an electromechanical device designed to blow cool or hot air over wet or damp hair, in order to accelerate the evaporation of water particles and dry the hair. Blowdryers allow to better control the shape and style of hair, by accelerating and controlling the formation of temporary hydrogen bonds inside each strand. These hydrogen bonds are very powerful (allowing for stronger hair shaping than even the sulfur bonds formed by permanent waving products), but are temporary and extremely vulnerable to humidity. They disappear with a single washing of the hair.
The normal use of a hairdryer
Hairstyles using blowdryers usually have volume and discipline, which can be further improved by the use of styling products and hairbrushes during drying to add tension, hold and lift.
Blowdryers were invented around the end of the 19th century. The first model was created by Alexander F. "Beau" Godefroy in his salon in France in 1890. The handheld, household hair-dryer first appeared in 1920. Blowdryers are used both in the beauty salon by professional stylists, and in the average household by consumers.
Hairdryer made by AEG, about 1935
Before the invention of the hair dryer, it was common for men and women to dry their hair using a vacuum cleaner. In fact, the original model of hairdryer was invented in 1890 by Alexander Godefroy by taking inspiration from the vacuum cleaner. Alexander invented it for usage in his hair salon in France and it was not portable or handheld, but instead could only be used by having the woman sit underneath it. A hair hood dryer has a hard plastic dome that comes down and fits over a person's head in order to dry their hair. Hot air is blown out through the tiny openings around the inside of the dome so the person's hair is dried evenly. Today hair hood dryers are mainly found in hair salons.
It was Armenian American inventor Gabriel Kazanjian who patented the first blow dryer in America in 1911.
It was not until around 1915 that the hair dryer began to go on the market in handheld form. This was due to innovations by National Stamping and Electricworks under the white cross brand (advertised here in 1915, and later U.S. Racine Universal Motor Company and the Hamilton Beach Co. that allowed the hair dryer to be handheld. Even in the 1920s, the new hair dryers were often heavy, weighing in at approximately 2 pounds (0.91 kg), and difficult to use. They also had many instances of overheating and electrocution. It was also only capable of using 100 watts, so it took a lot longer to dry hair (the average hairdryer today can use up to 2000 watts of heat).
Since the 1920s, development of the hairdryer has mainly focused on improving the wattage and superficial exterior and material changes. In fact, the mechanism of the hairdryer has not had any significant changes since its inception. One of the more important changes for the hairdryer is having the materials change to plastic so that it is more lightweight. This really caught on in the 1960s with the introduction of better electrical motors and the improvement of plastics. Another important change happened in 1954 when GEC changed the design of the dryer to move the motor inside the casing. Also, including safety mechanisms in them has been important, especially since Consumer Product Safety Commission set up guidelines in the 1970s that hairdryers had to meet in order to be considered safe to manufacture. Since 1991 the CPSC has mandated by U.S. law that all dryers must use a ground fault circuit interrupter so that it cannot electrocute a person if it gets wet. By 2000, deaths by blowdryers had dropped to less than four people a year, a stark difference to the hundreds of cases of electrocution accidents during the mid-twentieth century. In terms of positive health, this type of hairdryer has also been cited as an effective treatment for head lice. Overall, the size, weight, noise, and appearance of the hairdryer has dramatically changed from the heavy bulky noisy contraptions of the early part of the twentieth century, to the streamlined plastic that people are used to today.
There are two other major types of blowdryers other than the handheld. These are the bonnet hairdryer and the rigid-hood hairdryer. The bonnet hairdryer was introduced to consumers in 1951. This type of dryer worked by having the dryer, usually in a small portable box, connected to a tube that went into a bonnet with holes in it that could be placed on top of a person's head. This worked by giving an even amount of heat to the whole head at once. The 1950s also saw the introduction of the rigid-hood hair dryer which is the type most frequently seen in salons, and it had a hard plastic helmet that goes over the head. This dryer works similarly to the bonnet hairdryer but at a much higher wattage.
An early blow dryer
Most models use coils of wire that have a high electric resistivity and heat rapidly with an electric current. A fan (usually powered by a universal motor) blows ambient air past the hot coils resulting in heated air effective for drying. The heating element in most hairdryers is a bare, coiled nichrome wire that is wrapped around insulating mica heating boards. Nichrome wire is used in heating elements, because of two important properties: it is a poor conductor of electricity and it does not oxidize when heated.
In terms of modern models, a survey of stores in 2007 showed that most hair dryers have ceramic heating elements (like ceramic heaters)—because of their “instant heat” capability. This means that it takes less time for the dryers to heat up, so it takes a lot less time for the hair to dry.
Many of these hair dryers have “cool shot” buttons which turn off the heater and just blow room temperature air while the button is pressed. This function is useful in helping to maintain the hairstyle by setting it. The cold air also reduces frizz and can help to bolster the shine in the hair.
Many also feature “ionic” operation, to reduce the amount of static electricity build-up in the hair. Manufacturers also claim this makes the hair “smoother.” Some stylists[who?] today consider the introduction of ionic technology to be one of the most important advances in the beauty industry.
Hair dryers are available with different attachments, such as diffusers, airflow concentrators, and comb nozzle attachments. A diffuser is an attachment that is used on hair that is fine, colored, permed or naturally curly. It works by diffusing the heat so that the hair dries more slowly at a cooler temperature. This makes it so that the hair is less likely to frizz and it gives the hair more volume. An airflow concentrator does the exact opposite of a diffuser. It makes the end of the blowdryer more narrow and thus helps to concentrate the heat into one spot in order to make it dry rapidly. The comb nozzle attachment is the same as the airflow concentrator, but it ends with comb-like teeth so that the user can dry the hair using just the dryer without a brush or comb.
Hair dryers were first invented in 1931 by a man named John Tubir, an English immigrant that came to the United States by steam boat in 1911. John Tubir had a rare hair condition called "follicle moisture" which affected his hairs ability to grow. To help his condition, he invented the hair dryer so that he would be able to dry out so his hair follicles could once again be healthy. He sold his design to a manufacturer, and so began the enterprise of the hair dryer.
The History of Satellites
1. The invention of satellite Claudia Rojas
2. Early Work On Artificial Satellites Early on in the 20th century the work of Americans Robert Goddard and Russian Konstantin Tsiolkovsky paved the way for the future launchings of satellites. The theoretical work of Tsiolkovsky was on the actual possibility of launching this object into the upper regions of the atmosphere known as space. Taking this information Goddard did actual experimentation on how to launch such an object.
3. Dr. Robert H. Goddard Goddard was the first scientist who not only realized the potentialities of missiles and space flight but also contributed directly in bringing them to practical realization. This rare talent in both creative science and practical engineering places Goddard well above the opposite numbers among the European rocket pioneers. The dedicated labors of this modest man went largely unrecognized in the United States until the dawn of what is now called the "space age.“ High honors and wide acclaim, belated but richly deserved, now come to the name of Robert H. Goddard.
4. Konstantin Tsiolkovsky In 1926 Tsiolkovsky suggested the use of artificial earth satellites, including manned platforms, as way stations for interplanetary flight, and in 1929 he put forth an idea for a multistage rocket which he described as a rocket train.
5. Launch Of The First Satellite One autumn day in 1957 the launch of an 84 kg. ball revolutionized science. This ball was named Sputnik 1. It was launched on October 4,1957. This ball circled the earth in 1 hr. 36.2 min. at 28,800 km/h . It sent back strong continuous radio signals that were so strong that they could be picked up by amateurs. The US counterpart was named Explorer 1, it was launched on January 31, 1958. These two satellites provided an enormous boost for satellites to follow.
6. Satellites That Followed After that first launch many other satellites were sent into orbit which paved the way for major discoveries. 1. Sputnik 3 2. Cosmos 1 3. Cosmos 51 4. Cosmos 166 5. Explorer 1 6. Explorer 42 (Uhuru) These satellites made many great discoveries that have impacted on every part of our life.
7. How does it work? The figure shows a telemetry satellite that receives data for migration of turtles in the Caribbean Sea
8. Uses Of Satellites From navigation to high tech espionage the satellite has proved tremendously useful in their applications on everyday life. Since that first satellite that only sent back radio signals we now have satellites that accomplish a broad range of tasks. We now have satellites that support governments, give us high quality picture and sound on our televisions, ensure us faster beeps and better clarity on our cell phones. Ever since that autumn day in 1957 the satellite has advanced time and time again so that now it plays such an integral part of our everyday lives. How different our lives would be today without the vision of those that came before us.
9. Important Discoveries Made By Satellites From discovering the Van Allen radiation belts to the discoveries of x-rays in outer space the satellite has had a major impact on our everyday life. The first discovery that a satellite made was by Explorer1 in 1958. It was the first satellite to discover the Van Allen radiation belts that circled the earth. The next great discovery was the mapping of the x-rays of the universe. Explorer42 was the first to discover the source now called Cygnus x1. For the Russians the whole Cosmos series was devoted to discovering and mapping cosmic and ultraviolet sources within the universe. The work of these two countries stimulated the launch of satellites from such countries as ; Canada, China, India , and Japan. Thanks to all of these discoveries the satellite has become an accepted part of everyday life.
10. Conclusion In conclusion all of the groundwork that paved the way to the first launch made an impact on society as a whole that no other invention has done before. From communications to espionage to navigation to weather , this invention has shaped the way in which the world now lives. It is now an accepted part of everyday life. It is now seen as a useful tool which can be used to keep in touch and aid everyday life decisions. No invention in history has helped humankind on such a large basis as the satellite
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