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I always used to think that the drive across a four kilometre stretch from my house to the main road was a pain. Actually, not all of it was a pain. The car bounced up and down a few bumpy patches the first kilometer, then zoomed across a smooth 2.5 kilometre slope before struggling in a three-legged hurdle race at the final half kilometre. Reason: there was a traffic signal there and almost everyone in the world seemed to want to go somewhere at the same time....
Nine ‘o’ clock. It’s time for your favourite serial on television. Have you ever wondered how the same serial can be viewed by millions of people across the world? This is possible because of satellite television technology. It uses man-made or artificial satellites to send your favourite serial to your television set. But why do we need satellites for this purpose? How Does Satellite TV Work? The earth is round To understand this, we have to first take a look at the shape of our earth....
Two boys and two girls. They were to be found at one of the busiest traffic signals in south Delhi. The boys were about five or six years of age. The girls looked older, about eight or nine. As the traffic zipped along on the road, the four of them would play their own games on the divider. As soon as the traffic stopped on one side of the road, obeying the red signal, the children stopped their games....
Consider this, your state has been hit by a cyclone with wind speeds measuring 300 kilometres per hour. All modern means of communication – telephone, cellphone, wireless sets – lie dead as the cyclone has destroyed all connecting stations and links. This is what happened during the Orissa cyclone. All communication links broke down as dish antennas, radio stations, telephone lines, satellite links were destroyed. There was no way people could contact the outside world. This was when a bunch of amateurs, students and radio enthusiasts got together to set up something called an amateur radio or ham radio station....
Humans have invented new and advanced ways of communicating with each other. Television, radio, telephones and of course email. You will be surprised to know that animals who seem to have very simple methods of communication – using their bodies and voices – are also capable of long distance communication. How do Animals Communicate? [Illustration by Shinod AP] Foot stomping and low frequency rumbling created by elephants can travel upto 20 miles and is used by elephants to signal other herds or members, says an article in the Hindu newspaper....
Long before roads needed traffic lights, railways were using a system of signals to control train traffic. In the early railways, a single track was used for both up-going and down-going trains, and safety depended on spacing the arrival and departure of trains according to time intervals. These signals consisted of a ball and something that looked like a kite. When the kite was raised on top it indicated danger while if the ball was raised, it indicated the all clear....
Recently, sailors on the nuclear submarine that sank in the Baltic Sea were isolated from rescue workers as their radio set got damaged. Luckily their radio operators knew the Morse code and were able to communicate by knocking on the sides of the ship. There are many explanations for what the words stand for: Save Our Souls; Save Our Ship; Send Our Succour… The meaning of all three is the same – it is a plea for help by someone in distress....
Firefly is just a name. They are actually very cool insects. And they are not even flies, they are beetles. They have a way of sending out light signals every now and then. If you see them at night on a tree, you might think it is a brightly lit Christmas tree. That is the kind of light these fireflies produce. But the light they send out does not have heat, like the bulbs we use....
Do you believe that there might be life on other planets? Would you like to be the first ‘Earthling’ to make contact with an alien? Well, you can start your search from home. All you need is a computer and Internet access, and you can join the project of the US-based National Aeronautics and Space Administration (NASA). Logging on to Aliens [Illustrations by Kusum Chamoli] NASA launched the Search for Extra-Terrestrial Intelligence (SETI) project, eight years ago....
Most movie fans have seen or at least heard of Hollywood legends Hedy Lamarr and Steve McQueen. But how many know that these two were inventors who have significantly changed our lives. Nobody? Not surprising. But it’s true. Hedy Lamarr and Steve McQueen were both Hollywood stars and inventors. Hedy Lamarr thought of torpedoes guided by radio signals and Steve McQueen invented the bucket seat that has revolutionised the automobile industry. However, Hedy’s invention was never used for the purpose invented....
Source: https://www.pitara.com/tags/signals/
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