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1. Oriental inventors have created numerous things we take for granted in our daily lives.
eg. Oriental inventors are claimed to have created numerous things we take for granted in our daily lives.
2. Ulugbek, a famous astronomer, compiled tables of sines and tangents, accurate to eight decimal places.
A famous astronomer Ulugbek wrote accurate trigonometric tables of sines and tangents values correct to at least eight decimal places
3. In 860, the three sons of Musa ibn Shakir published the Book on Artifices, which described a hundred of technical constructions.
In 860, the three sons of Musa ibn Shakir published the Book on Artifices which described a hundred technical constructions.
4. Oriental horticulture gave the world the fragrant flowers and herbs from which perfumes were extracted.
5. In the fifteenth century Vasco da Gama, exploring the east coast of Africa, new Malindi, was guided by an oriental pilot, Ahmed ibn Majid who used maps never seen by Europeans before.
In the fifteenth century Vasco da Gama, exploring the east coast of Africa, new Malindi. New Malindi was guided by an oriental pilot, Ahmed ibn Majid who used maps never seen by Europeans before.
Ex 4. Write information about any invention and its inventor .
The Italian engineer Guglielmo Marconi (1896) is traditionally considered the creator of the first successful system for exchanging information using radio waves (radiotelegraphy). However, Marconi, like most of the authors of major inventions, had predecessors. In Russia, A.S. Popov, who created a practical radio receiver in 1895. In the United States, this is considered Nikola Tesla, who patented a radio transmitter in 1893 and a receiver in 1895; his priority over Marconi was recognized in court in 1943. In France, the inventor of the coherer (1890), Edouard Branly, has long been considered the inventor of wireless telegraphy. The first inventor of methods for transmitting and receiving electromagnetic waves (which for a long time were called "Hertzian Waves") is their discoverer, the German scientist Heinrich Hertz (1888).
Principle of operation
Transmission occurs as follows: a signal with the required characteristics (frequency and amplitude of the signal) is generated on the transmitting side. The transmitted signal then modulates a higher frequency waveform (carrier). The received modulated signal is emitted by the antenna into space. On the receiving side, radio waves induce a modulated signal in the antenna, after which it is demodulated (detected) and filtered by a low-pass filter (thereby getting rid of the high-frequency component - the carrier). Thus, a useful signal is extracted.
Propagation of radio waves
Ulugbek
The teenage ruler set out to turn the city into an intellectual center for the empire. Between 1417 and 1420, he built a madrasa ("university" or "institute") on Registan Square in Samarkand (currently in Uzbekistan), and he invited numerous Islamic astronomers and mathematicians to study there. The madrasa building still survives. Ulugh Beg's most famous pupil in astronomy was Ali Qushchi (died in 1474). Qadi Zada al-Rumi was the most notable teacher at Ulugh Beg's madrasa and Jamshid al-Kashi, an astronomer, later came to join the staff.[3]
Ulugh Beg and his astronomical observatory scheme, depicted on the 1987 USSR stamp. He was one of Islam's greatest astronomers during the Middle Ages. The stamp says "Uzbek astronomer and mathematician Ulugbek" in Russian.
Observatory built by Ulugh Beg in the 1420s. The site was later rediscovered by Russian archaeologists in 1908.[citation needed]
Astronomy piqued Ulugh Beg's interest when he visited the Maragheh Observatory at a young age. This observatory, located in Maragheh, Iran, is where the well-known astronomer Nasir al-Din al-Tusi practised.[4]
Ulugh Beg Observatory in Samarkand. In Ulugh Beg's time, the walls were lined with polished marble.
In 1428, Ulugh Beg built an enormous observatory, similar to Tycho Brahe's later Uraniborg as well as Taqi al-Din's observatory in Constantinople. Lacking telescopes to work with, he increased his accuracy by increasing the length of his sextant; the so-called Fakhri sextant had a radius of about 36 meters (118 feet) and the optical separability of 180" (seconds of arc). The Fakhri sextant was the largest instrument at the observatory in Samarkand (an image of the sextant is on the side of this article). There were many other astronomical instruments located at the observatory, but the Fakhri sextant is the most well-known instrument there. The purpose of the Fakhri sextant was to measure
the transit altitudes of the stars. This was a measurement of the maximum altitude above the horizon of the stars. It was only possible to use this device to measure the declination of celestial objects.[12] The image, which can be found in this article, shows the remaining portion of the instrument, which consists of the underground, lower portion of the instrument that was not destroyed. The observatory built by Ulugh Beg was the most pervasive and well-known observatory throughout the Islamic world.[3]
With the instruments located in the observatory in Samarkand, Ulugh Beg composed a star catalogue consisting of 1018 stars, which is eleven fewer stars than are present in the star catalogue of Ptolemy. Ulugh Beg utilized dimensions from al-Sufi and based his star catalogue on a new analysis that was autonomous from the data used by Ptolemy.[13] Throughout his life as an astronomer, Ulugh Beg came to realize that there were multiple mistakes in the work and subsequent data of Ptolemy that had been in use for many years.[2]
Using it, he compiled the 1437 Zij-i-Sultani of 994 stars, generally considered[who?] the greatest star catalogue between those of Ptolemy and Tycho Brahe, a work that stands alongside Abd al-Rahman al-Sufi's Book of Fixed Stars. The serious errors which he found in previous Arabian star catalogues (many of which had simply updated Ptolemy's work, adding the effect of precession to the longitudes) induced him to redetermine the positions of 992 fixed stars, to which he added 27 stars from Abd al-Rahman al-Sufi's catalogue Book of Fixed Stars from the year 964, which were too far south for observation from Samarkand. This catalogue, one of the most original of the Middle Ages, was first edited by Thomas Hyde at Oxford in 1665 under the title Tabulae longitudinis et latitudinis stellarum fixarum ex observatione Ulugbeighi and reprinted in 1767 by G. Sharpe. More recent editions are those by Francis Baily in 1843 in vol. xiii of the Memoirs of the Royal Astronomical Society and by Edward Ball Knobel in Ulugh Beg's Catalogue of Stars, Revised from all Persian Manuscripts Existing in Great Britain, with a Vocabulary of Persian and Arabic Words (1917).
In 1437, Ulugh Beg determined the length of the sidereal year as 365.2570370...d = 365d 6h 10m 8s (an error of +58 seconds). In his measurements over the course of many years he used a 50 m high gnomon. This value was improved by 28 seconds in 1525 by Nicolaus Copernicus, who appealed to the estimation of Thabit ibn Qurra (826–901), which had an error of +2 seconds. However, Ulugh Beg later measured another more precise value of the tropical year as 365d 5h 49m 15s, which has an error of +25 seconds, making it more accurate than Copernicus's estimate which had an error of +30 seconds. Ulugh Beg also determined the Earth's axial tilt as 23°30'17" in the sexagesimal system of degrees, minutes and seconds of arc, which in decimal notation converts to 23.5047°.[14]
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