Evolution of Time-keeping Devices in 3 minutes скачать в хорошем качестве

Evolution of Time-keeping Devices in 3 minutes

How innovations in computation and machine revolutionized time-keeping devices. This concise video on time-keeping devices was created by Kuo Xing, Francis Charles and Murali Sabapathy for academic purposes. Special thanks go to our lecturer and tutor for their inspirations and guidance. Transcript: "We keep track of time almost every day in our lives, whether it is our sleep, leisure, work, school, and even our dreadful… deadlines! But have you ever wondered how time was counted in the past? The earliest time-keeping devices relied on the sun. The first sundials were simply sticks placed in the ground that showed time by length and direction of the resulting shadow. In 1500 B.C., Egyptians made a more advanced sundial. A T-shaped bar placed in the ground, dividing between sunrise and sunset into 12 parts. These 12 parts came about based on the Egyptian’s use of the duodecimal system, with a base of 12. 12 because it equals the number of finger joints on each hand. Using the thumb to count each finger joints, we have 3 times 4, equalling to 12 for one hand! The water clock, was invented soon after the dial by an Egyptian pharaoh in 1400 B.C. It was perhaps the most accurate timekeeping device of the ancient world. In fact, Plato, the legendary Greek philosopher, created the alarm clock through the use of the water clock. As water filled up the reservoir, it blew a whistle that disturbed his awesome sleep. Later in 500, the candle clock was invented. This candle has evenly spaced markings on it which indicates the duration of time that has passed since it was first lit. King Alfred the great, in the 9th century, used this system with 6 candles, each was 12 inches high and could burn up to 4 hours, lasting a total of 24 hours. Then the mechanical clocks arrived. The first clock was built in the 11th century by Pope Sylvester the Second. Galileo Galilei, father of science, experimented the pendulum which was a way of marking off small intervals of time accurately. It took 50 years for a pendulum clock to be built, resulting in a massive leap in the evolution of time-keeping devices. Towards the 19th to 20th century, world wars started to occur. Wristwatches were first worn by military men towards the end of the nineteenth century, when there was an importance of synchronizing wartime-actions without potentially revealing the plan to enemies. To make these devices more accurate, Quartz Watches were then invented in 1927. Quartz crystals, together with its piezoelectric ability, made them the most accurate time-keeping devices in the 1930s. Its accuracy is within a few seconds per year. Nearly 40 years later, the first atomic clock was built, creating a new time standard. The caesium element was used to measure time. 1 second represented 9,192,631,770 oscillations of caesium atom’s resonant frequency, making these clocks extremely accurate within a second over many thousands of years. With advanced technology nowadays, time can be tracked on our mobile phones, computers, smart watches which synchronizes time through cell signal or the internet. Why do our devices still have slightly different times?! It’s because, servers use different versions of atomic clocks and time-keeping devices. Thus, there is no 1 standardized source of time in the world currently. So… how should we go on from here...?" Article References: http://www.scientificamerican.com/art... http://content.time.com/time/business... Video References: https://www.youtube.com/watch?v=At5at... https://www.youtube.com/watch?v=PXiyq... GEK1536 / GEH1017