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History Of Computers Questions and answers 1. What was the worlds first recognised calculating device? How did it work? Insert a picture of it. The world’s first recognised calculating device was the ABACUS. This consisted of a series of rows of beads on wires, with each row showing place values. 2. When was the first mechanical calculating device thought to be have been developed and by which group of people. This was an important archaeological find in 1900. The first mechanical calculating device was thought to have been developed by the Greeks over 2000 years ago. It was designed to record the planets motions. 3. What were the first analog calculating devices generally used for. ( Ancient Times) They were designed to calculate planetary motion as well as to forecast lunar and solar eclipses. 4. When was the first known digital calculating device built? Who designed it and what was it used for? How did it work? (French) In 1642 the French mathematician and physicist Blaise Pascal built and patented a general-purpose digital calculator, capable of addition and subtraction. He used wheels engraved with the numbers 0 to 9 and his device is classed as digital because notches on the wheels ensured they always stopped with the pointer against a definite number. The first wheel stored the units; the second wheel the tens, the third the hundreds and so on. After one number had been entered, another could be added by turning the wheels appropriately. When any wheel was advanced beyond 9 an internal ratchet moved the next wheel one place forward, thus automatically transferring the carry figure. Subtraction was performed by the addition of complements as described in chapter 2. Advertising his calculator, Pascal wrote: "I submit to the public a small machine of my own invention, by means of which you alone may, without any effort, perform all the operations of arithmetic, and may be relieved of the work which has often times fatigued your spirit.’ 5. Not long after Q4. was built a person of Germanic origins extended his ideas. What was the nature of the extension and who was the person who did this? When did it happen? In 1673 the German philosopher and mathematician Gottfried Leibniz devised a machine which could also do multiplication by repeated addition and division by repeated subtraction. Leibniz expressed the need for calculators when he wrote: "It is unworthy of excellent men to lose hours like slaves in the labour of calculation which could safely be relegated to anyone else if machines were used". The key to his design was a "stepped wheel" comprising a cylindrical drum with nine teeth of varying length. A small pinion wheel engaged a varying number of teeth, depending on its position. His calculator still drew heavily on the work of Pascal, nevertheless Leibniz couldn't resist a side thrust at the Frenchman when he commented: "Pascal's machine is an example of the most fortunate genius but while it facilities only additions and subtractions, the difficulty of which is not very great in themselves, it commits multiplication and division to a previous calculation so that it commended itself rather by refinement to the curious than as of practical use to people engaged on business affairs". Despite these comments the machine of Leibniz, like that of Pascal, was an economic failure. 6. During the 18th Century a machine was invented that could do square roots as well as the other mathematics. Who developed this? During the 18th century several further designs appeared, including a remarkable one by the Polish inventor Abraham Stern that could find square roots to six digits. Commercial manufacture of mechanical desk calculators began early in the l9th century and continued until about 1960. 7. In 1805, the first storage device was developed. Who invented it, what was it and how did it work? In 1805 a Frenchman, Joseph Jacquard, invented an attachment for a weaving loom which essentially automated the process of weaving fabrics with complicated designs. He used a series of cards, with holes punched in them, to determine the woven pattern. Each hole allowed a hook to pull up a thread of the warp, so that the shuttle these threads and over the others. A different card was used for each pass of the shuttle. If the weaver later substituted threads of different colours, the punched cards ensured that the form of the pattern remained precisely the same. Thus the punched cards provided program storage; a concept essential to a computer. As holes were either present or absent at each location on the cards, the program information was stored in a binary form. It is interesting to note that this technological breakthrough was accepted so rapidly that within a decade more than 10,000 looms in France had been adapted to incorporate the new automation. After Jacquard's death grateful workers wove his portrait on one of his machines, using no fewer than 24,000 punched cards and producing a result which because of its fine detail was often mistaken for an engraving. 8. What happened in 1833?
Approximate Word count = 3375
Approximate Pages = 13.5
(250 words per page double spaced)
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