100 Amazing Inventions
61. What is satellite radio?
SATELLITE RADIO:
For decades, to listen to radio entertainment, you had two choices - AM radio and FM radio. But in the last few years, an entirely new way to listen to radio has emerged satellite radio.
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| Sirius Radio |
This kind of radio broadcasting is digital. It is broadcast via a communication satellite that gives a wider range. Two companies got the the license to provide satellite radio in the year 1997. They were XM and Sirius.
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| XM Radio |
Satellite radio was officially launched in the year 2001. One of the great advantages of satellite radio is the fact that the programmes are not interrupted by commercials. This is because the provider's income comes from listeners, who pay for the service, and not from advertisers. The satellite radio signal is digital, which means that you will get crystal clear sound wherever you go.
62. Why is scramjet a remarkable invention?
SCRAMJET:
During, and after World War II, tremendous amounts of time and effort were put into researching high-speed jet and rocket powered aircraft.
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| Scramjet |
Scramjet is an engine technology that is aimed at cutting weight. Airplane and rocket fuel requires oxygen to combust. But at very high altitudes, oxygen is also rather scarce. Therefore, when flying in the stratosphere, rocket engines generally need to carry their own oxygen to use as fuel.
Scramjet technology is designed to eliminate the need to carry oxygen. The oxygen needed by the engine to combust is taken from the atmosphere passing through the vehicle, instead of from a tank on-board. The craft becomes smaller, lighter and faster.
Moreover, since a scramjet has no rotating part, it is easier to manufacture than conventional jet engines. At high altitudes, scientists estimate that scramjet powered aircraft could reach theoretical speeds of anywhere from Mach 12 to Mach 24!
63. What is a Blu-ray?
BLU-RAY:
Blu-ray is the name of a new optical disc format. The format was developed to enable recording, rewriting, and playback of high definition video, as well as storing large amounts of data.
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| Blu-ray Disc |
The format offers more than five times the storage capacity of traditional DVDs. While current optical disc technologies such as DVDs rely on a red laser to read and write data, the new format uses a blue-violet laser instead, hence the name Blu-ray.
The benefit of using a blue-violet laser is that it has a shorter wavelength than a red laser. This makes it possible to focus the laser spot with even greater precision.
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| A Collection of Blu-ray discs |
As a result, data can be packed more tightly, and stored in less space. Therefore, it's possible to fit more data on a Blu-ray disc, even though it's the same size as a CD or DVD.
64. Why is Skype so popular?
SKYPE:
Skype is an application for doing things together, whenever you're apart. It provides video, chat, and voice call services that make it simple to share experiences with the people that matter to you, wherever they are.
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| Skype Calling |
Skype made its first appearance in 2003, and was the brainchild of Niklas Zennstrom, Dane Janus Friis, Ahti Heinla, Priit Kasesalu and Jaan Tallinn. It allows users to communicate over the Internet by voice using a microphone, by video by using a webcam, as well as with instant messaging.
With Skype, you can share a story, celebrate a birthday, learn a language, hold a meeting, work with colleagues - just about anything you need to do together everyday.
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| Skype Logo |
You can use Skype on whatever works best for you - on your phone or computer or a TV with Skype on it and best of all, its a free service.
Skype had more than 663 million registered users by the year 2010. In March 2020, Skype was used by 100 million people on a monthly basis and by 40 million people on a daily basis.
65. What is the importance of graphene?
GRAPHENE:
In simple terms, graphene, is a thin layer of pure carbon. It is a single, tightly packed layer of carbon atoms that are bonded together in a hexagonal honeycomb lattice.
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| Graphene 2D structure |
It is the thinnest compound known to man, for it is only one atom thick. It is one of the lightest material known and the strongest compound discovered, being between 100-300 times stronger than steel.
Graphene is also the best conductor of electricity. It is stretchable, and yet is almost transparent. It conducts heat better than any other known substance. It acts as a barrier to the smallest atom of gas - helium - and yet allows water vapour to pass through. Although scientists knew one atom thick, two dimensional crystal graphene existed, no-one had worked out how to extract it from graphite.
That was until it was isolated in 2004 by two researchers at the University of Manchester, Professor Andre Geim and Professor Kostya Novoselov.
The potential uses for graphene appear almost limitless. They range from new types of flexible electronics that could be worn on clothes or folded up into a pocket, to a new generation of very small computers, and super fast mobile phones.