- published: 26 Nov 2013
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A quartz clock is a clock that uses an electronic oscillator that is regulated by a quartz crystal to keep time. This crystal oscillator creates a signal with very precise frequency, so that quartz clocks are at least an order of magnitude more accurate than good mechanical clocks. Generally, some form of digital logic counts the cycles of this signal and provides a numeric time display, usually in units of hours, minutes, and seconds. Quartz timekeepers are the world's most widely-used timekeeping technology, used in most clocks and watches, as well as computers and other appliances that keep time.
Chemically, quartz is a compound called silicon dioxide. Many materials can be formed into plates that will resonate. However, quartz is also a piezoelectric material, that is, when bent, it develops electrical charges across some planes in its crystal. In a reverse effect, if charges are placed across the crystal plane, quartz crystals will bend. Since quartz can be directly driven (to flex) by an electric signal, no additional speaker or microphone is required to use it in a resonator. Similar crystals were once used in low-end phonograph cartridges: The movement of the stylus (needle) would flex a quartz crystal, which would produce a small voltage, which was amplified and played through speakers. Quartz microphones are still available, though not common.
James Daniel May (born 16 January 1963) is an English television presenter, journalist and writer. He is best known for his role as co-presenter of the award-winning motoring program Top Gear alongside Jeremy Clarkson , and Richard Hammond.
On Top Gear, May has the nickname "Captain Slow" for his careful driving style, a love of small underpowered cars and habit of getting lost and distracted while driving. However, in a July 2010 episode of Top Gear he drove a Bugatti Veyron Super Sport, reaching a speed of 417.6 kilometres per hour (259.5 mph). After his attempt the Bugatti test driver Pierre-Henri Raphanel took the car to 430 kilometers per hour (267.5 mph).
May has presented a variety of other programs on themes including science and technology, toys, cars, wine culture, and the plight of manliness in modern times. In addition he has released a variety of DVDs and books with similar themes, and wrote a weekly column for The Daily Telegraph's motoring section.
James May was born in Bristol, one of four children; he has two sisters and a brother. May attended Caerleon Endowed Junior School in Newport, then in Monmouthshire. He spent his teenage years in South Yorkshire where he attended Oakwood Comprehensive School in Rotherham and was a choirboy at Whiston Parish Church. He was also at school with Life On Mars and Ashes to Ashes star Dean Andrews. A keen flautist and pianist, he later studied music at Pendle College, Lancaster University. After graduating, May briefly worked at a hospital in Chelsea as a records officer, and had a short stint in Her Majesty's Civil Service.