Search results
Results from the WOW.Com Content Network
The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.
Archimedes' achievements in this area include a proof of the law of the lever, [10] the widespread use of the concept of center of gravity, [11] and the enunciation of the law of buoyancy known as Archimedes' principle. [12] In astronomy, he made measurements of the apparent diameter of the Sun and the size of the universe.
The Claw of Archimedes (Ancient Greek: Ἁρπάγη, romanized: harpágē, lit. 'snatcher'; also known as the iron hand ) was an ancient weapon devised by Archimedes to defend the seaward portion of Syracuse 's city wall against amphibious assault .
Image credits: Isabella Thornton #2 An Early Motorised Scooter. The Autoped was an early vision of today's scooters. This was a personal transport system originally developed in 1915.
Archimedes is purported to have invented a large scale solar furnace, sometimes described as a heat ray, and used it to burn attacking Roman ships during the Siege of Syracuse (c. 213–212 BC). It does not appear in the surviving works of Archimedes and there is no contemporary evidence for it, leading to modern scholars doubting its existence.
Method of exhaustion: Formalized by Eudoxus of Cnidus in the early 4th century BC, used by Archimedes to calculate the value of pi and the area under a curve. [95] Mathematical proof: The mathematical proof was a product of Greek mathematics, evolving gradually to reach the method still used today in Euclid's Elements around 300 BC. [96]
Here are nine of the accidental inventions we use every day. Skip to main content. 24/7 Help. For premium support please call: 800-290-4726 more ways to reach us. Sign in ...
Following Archimedes's estimate of a myriad (10,000) grains of sand in a poppy seed; 64,000 poppy seeds in a dactyl-sphere; the length of a stadium as 10,000 dactyls; and accepting 19mm as the width of a dactyl, the diameter of Archimedes's typical sand grain would be 18.3 μm, which today we would call a grain of silt. Currently, the smallest ...