How do Telephones work?

The way that Telephones work is similar in some ways to television, but the transmission uses an electric current rather than air waves, and telephones transmit only sound, not pictures.

When you speak on the Telephone, the microphone inside the mouthpiece transforms the sound waves into electrical impulses. These are transmitted through the telephone cable to the ear piece of the other person’s receiver. This turns the impulses into sounds which are nearly identical to those made by the caller, so that it is like listening to the actual voice of the person talking.

Years ago, and still today in some isolated places, you had to ask the operator or at the telephone exchange to connect your telephone with someone else’s in order to speak to them. Nowadays, thanks to the progress of electronics, the connection is made automatically, even to countries on the other side of the world.

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How an Electronic Calculator Works?

The operations of an electronic calculator are not only very quick, they are also very basic. Most of the calculations are done using simple addition and subtraction, and a number system which has only two numbers, 0 and 1.
This binary (two-state) number system is used in calculators and other electronic devices, because they operate on a system of electronic switches, which at any time can only be in one of two states; off or on. In the Binary code, ‘off is represented by 0, and ‘on’ by 1.
The calculator keyboard uses our usual (decimal) numbers, from 0 up to 9, on its keys, but when a key is pushed down, the calculator understands this in the binary equivalent, which is fed through a ‘switch point’ situated under the key, and from there into the heart of the calculator – the ‘chip’.
This is a tiny integrated circuit, an incredible network of electronic components in a piece of Silicon, itself smaller than a Do stage stamp.
The chip carries out the binary operations at the speed of light, and its answers are sent back to the display, and its answers are sent back to the display. The Calculator converts binary into decimal again, using a ‘decoder’ (a circuit based on switches),and these decimals appear on the display panel, using LED, or light emitting diode, segments.
The space for each unit on the display has seven such segments, plus a decimal point, and each LED gives off a reddish glow when required. Different combinations of these segments light up any decimal number from 0 up to 9, as the chip instructs through the switching circuit.
The chip adds in the standard binary way: 0+1 = 1; 0+) = 0’ and 1=1 = 0 (equivalent of 2). And it subtracts by reversing this procedure.
The operations of multiplication and division are carried out by continued addition and subtraction, respectively. For example, to multiply 43 by 17, the calculator adds 43 seventeen times. This may seem show to us, but electronically the answer is arrived at almost immediately.
Just try dividing 1,089 by 33, and see how long you take! How would the calculator solve this one? And because it works electronically, it can do harder sums in about the same amount of time. It would divide 582.31 by 34.9 as soon as add two and two!

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Which language is spoken by most people?

Over 500 million people speak one of the Mandarin Chinese dialects. Chinese is unlike most other languages as it has no alphabet, but uses instead several thousand characters or symbols, each of which conveys one complete idea. Each character has only one syllable, and most words are made up of two or more characters. A character can change its meaning by the way its pronounced or by changing its position in a sentence, It is only in the last hundred years that ways have been invented to write Chinese in the Roman alphabet.

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Why is playing important?

Some adults think that when children play they are wasting their time and that it is more important to study. They couldn’t be more wrong. Children need to play both by themselves and with others as they develop their personalities this way. Babies, especially, learn through playing, and children’s games change as they grow up, until they reach an age where they are gradually replaced by other activities and pastimes. Adults do not play in the same way as children, but they also need leisure interests – more than ever now that working hours are less – both to amuse themselves and to relax.

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