Hearing Impairment Series-Disabled Legend Guillaume Amontons

Guillaume Amontons was born on 31 August, 1663 in Paris, France and died on 11 October, 1705 in Paris, France. Guillaume was a French scientific instrument inventor and physicist. Guillaume was one of the pioneers in tribology, apart from Leonardo da Vinci, John Theophilius Desanguliers, Leonard Euler and Charles-Augustin de Coulomb.

Guillaume’s father was a lawyer from Normandy who had moved to the French capital. While still young, Guillaume lost his hearing, which may have motivated him to focus entirely on science. Guillaume never attended a university, but was able to study mathematics, the physical sciences, and celestial mechanics. Guillaume also spent time studying the skills of drawing, surveying, and architecture. Guillaume was supported in his research career by the government, and was employed in various public works projects.

Among his contributions to scientific instrumentation were improvements to the barometer (1695), hygrometer (1687), and thermometer (1695), particularly for use of these instruments at sea. Guillaume also demonstrated an optical telegraph and proposed the use of his clepsydra (water clock) for keeping time on a ship at sea.

Guillaume investigated the relationship between pressure and temperature in gases though he lacked accurate and precise thermometers. Though his results were at best semi-quantitative, he established that the pressure of a gas increases by roughly 1/3 between the temperatures of cold and the boiling point of water. This was a substantial step towards the subsequent gas laws and, in particular, Charles’s law.

Guillaume’s work led him to speculate that a sufficient reduction in temperature would lead to the disappearance of pressure. Thus, he is the first researcher to discuss the concept of an absolute zero of temperature, a concept later extended and rationalised by William Thomson, 1st Baron Kelvin. In 1699, Guillaume published his rediscovery of the laws of friction first put forward by Leonardo da Vinci. Though they were received with some scepticism, the laws were verified by Charles-Augustin de Coulomb in 1781.

Leonardo da Vinci (1452-1519)) can be named as the father of modern tribology as he studied an incredible manifold of tribological subtopics such as: friction, wear, bearing materials, plain bearings, lubrication systems, gears, screw-jacks, and rolling-element bearings. 150 years before Guillaume’s Laws of Friction were introduced, he had already recorded them in his manuscripts. Hidden or lost for centuries, Leonardo da Vinci’s manuscripts were read in Spain a quarter of a millennium later.

Guillaume’s Laws of Friction were first recorded in books during the late 17th century.

There 3 laws of friction are:

  • 1. The force of friction is directly proportional to the applied load. (Guillaume’s 1st Law)
  • 2. The force of friction is independent of the apparent area of contact. (Guillaume’s 2nd Law)
  • 3. Kinetic friction is independent of the sliding velocity. (Coulomb’s Law)

NOTE: These 3 laws only apply to dry friction, in which the addition of a lubricant modifies the tribological properties signifiantly.

By looking at any surface on the microscopic level, one would find that it is never perfectly flat. There would exist many tiny bumps and craters, due to imperfections on the surface and the alignment of molecules. (The skin does not feel the bumps and craters because they are too small to be detected.) Considering a smooth stone on a smooth flat road, the 2 surfaces would be still in contact, but only at a few points (the bumps do fot fit exactly into the craters). Due to electrostatic forces of repulsion between the atoms (nuclei and nuclei) of the stone and the road, the road will exert a force on the stone, and the stone will exert a force on the road (normal contact forces). The NET force exerted on the stone would be the NORMAL contact force.

If net external forces cause the stone to move to the RIGHT, the forces that the road exert on the stone would be slightly skewed to the LEFT, thus the net force will be pointing UP but LEFTWARD (tilted contact force). As the vertical component of the net force is the normal contact force, the extra horizontal leftward component of the force would therefore be the FRICTIONAL force. (Note: friction OPPOSES motion)

Suppose the stone had a greater mass (hence greater weight as g=constant). The stone would then:

  • exert a greater force on the road (the increased load causes the separation distance of the nuclei to decrease, force of repulsion becomes stronger(inverse-square law) ), AND
  • more of the atoms of the road and the stone would be in contact.

Hence, when the stone is moved, a greater frictional force would be produced (more areas of contact means that more forces can be skewed, producing more horizontal components of the contact forces).

Guillaume’s law applies to any 2 surfaces, regardless of their orientation. (e.g. pressing a brick against the ceiling, etc.)

NOTE: Applied load means the normal contact force acting on the stone. That is, if the stone is being pushed down harder while it was trying to move, the force acting on the ground increases, and hence the force of the ground acting on the stone (normal contact) increases. This means that more force is required to move the stone across the ground. (frictional force increase)

What this law means is that if two equal masses made of similar material are resting on the same surface with DIFFERENT SURFACES AREAS OF CONTACT, they would require the SAME AMOUNT of FORCE to start moving (overcome static friction) and to move at constant speed+.

To put it in another way: considering 2 equal masses, and the area in contact in situation A is greater than in situation B. This only means that in situation A, the load is distributed across a greater area then in situation B. However, the applied load is still the same! Thus to move both masses, we would require the same amount of applied force to overcome friction. (Guillaume’s First Law)

+ To maintain constant speed, net force has to be 0N. Assuming no drag forces,
 \begin{align} F_{applied}-F_{fric} & = 0 \\ \therefore F_{applied} & = F_{fric} \\ \end{align}

Through studies and experimental observations on the properties of friction, a relationship between frictional force and normal contact force was established:

\begin{align}F_{fric}=\mu N\end{align},

where μ is the coefficient of friction and N is the normal contact force.

This is as predicted by Guillaume’s 2 laws, where Ffric depends only on the normal contact force (reaction pair of the applied load), and is independent of the surface area in contact.

However, exceptions to Guillaume’s Law have been observed in various nanometric scenarios. For example, when 2 surfaces get close enough such that molecular interactions and atomic forces come into play, the 2 surfaces are attracted together and form what was known as ‘negative load’.

*requires verfication by Specialists*

Honours:

  • Member, Académie des Sciences, (1690)
  • The Amontons crater on the Moon is named after him.

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Hearing Impairment Series-Disabled Legend Pete Townshend

Peter Dennis Blandford Townshend was born on 19 May 1945 in Chiswick, London. Pete Townshend is an award-winning English rock guitarist, singer, songwriter, composer, and writer, known principally as the guitarist and songwriter for The Who, as well as for his own solo career. Pete Townshend’s career with The Who spans more than 40 years, during which time the band grew to be considered one of the most influential bands of the rock era, in addition to being “possibly the greatest live band ever.

Pete Townshend is the primary songwriter for the Who, writing well over 100 songs for the band’s 11 studio albums, including the rock operas Tommy and Quadrophenia, plus dozens more that appeared as non-album singles, bonus tracks on reissues, and tracks on rarities compilations such as Odds and Sods. Pete has also written over 100 songs for his solo albums and rarities compilations. Although known mainly for being a guitarist, he is also an accomplished singer and keyboard player, and has played many other instruments on his solo albums, and on some Who albums (such as banjo, accordion, synthesizer, piano, bass guitar, drums).

Pete has also written newspaper and magazine articles, book reviews, essays, books, and scripts.

Born into a musical family (his father Cliff Townshend was a professional saxophonist in The Squadronaires and his mother Betty a singer), Pete Townshend exhibited a fascination with music at an early age. Pete Townshend had early exposure to American Rock and Roll (his mother recounts that he repeatedly saw the 1956 film Rock Around the Clock and obtained his first guitar from his grandmother at the age of 12, which he described as a “Cheap Spanish thing”. Townshend’s biggest guitar influences include Link Wray, John Lee Hooker, Bo Diddley and Hank Marvin of The Shadows. 

In 1961Pete Townshend enrolled at Ealing Art College, and a year later he and his school friend from Acton County Grammar School John Entwistle founded their first band, The Confederates, a Dixieland duet featuring Pete Townshend on banjo and Entwistle on horn. From this beginning they moved on to The Detours, a skiffle/rock and roll band fronted by then sheet-metal welder Roger Daltrey. In early 1964, due to another band having the same name, The Detours renamed themselves The Who. Drummer Doug Sandom was replaced by Keith Moon not long afterwards. The band (now comprising Daltrey on vocals and harmonica, Pete Townshend on guitar, Entwistle on bass, and Moon on drums) were soon taken on by a mod publicist (named Peter Meaden) who convinced them to change their name to The High Numbers to give the band more of a mod feel. After bringing out one single (“Zoot Suit”), they dropped Meaden and were signed on by two new managers, Chris Stamp and Kit Lambert. They dropped The High Numbers name and reverted to The Who.

Pete Townshend met Karen Astley (daughter of composer Ted Astley) while in art school and married her in 1968. The couple separated in 1994 and Pete Townshend announced they would divorce in 2000. They have 3 children Emma born in 1969, who is a singer/songwriter, Aminta born in 1971 and Joseph born in 1989. For many years Pete Townshend refused to confirm or deny rumors that he was bisexual. In a 2002 interview with Rolling Stone magazine, however, he explained that, although he engaged in some brief same-sex experimentation in the 1960s, he is hetrosexual. Pete Townshend currently lives with his long-time partner, musician Rachel Fuller, in Richmond, England. Pete Townshend also owns a house in Churt, Surrey, England.

Pete Townshend has woven a long history of involvement with various charities and other philanthropic efforts throughout his career, both as a solo artist and with The Who. Pete’s  first solo concert, for example, was a 1974 benefit show which was organized to raise funds for the Camden Square Community Play Center.

The earliest public example of Pete Townshend’s involvement with charitable causes is the relationship he established with the Richmond-based Meher Baba Association. In 1968, Pete Townshend donated the use of his former Wardour Street apartment to the Meher Baba Association. The following year, the association was moved to another Townshend-owned apartment, the Eccleston Square former residence of wife Karen.

Pete Townshend sat on a committee which oversaw the operation and finances of the center. “The committee sees to it that it is open a couple of days a week, and keeps the bills paid and the library full,” he wrote in a 1970 Rolling Stone article.

In 1969 and 1972 Pete Townshend produced 2 limited-release albums, Happy Birthday and I Am, for the London-based Baba association. This led to 1972’s Who Came First, a more widespread release, 15 percent of the revenue of which went to the Baba association. A further limited release, With Love, was released in 1976. A limited-edition boxed set of all 3 limited releases on CD, Avatar, was released in 2000, with all profits going to the Avatar Meher Baba Trust in India, which provided funds to a dispensary, school, hospital and pilgrimage center.

In July 1976, Pete Townshend opened Meher Baba Oceanic, a London activity centre for Baba followers which featured film dubbing and editing facilities, a cinema and a recording studio. In addition, the centre served as a regular meeting place for Baba followers. Pete Townshend offered very economical (reportedly £1 per night) lodging for American Baba followers who needed an overnight stay on their pilgrimages to India. “For a few years, I had toyed with the idea of opening a London house dedicated to Meher Baba,” he wrote in a 1977 Rolling Stone article. “In the 8 years I had followed him, I had donated only coppers to foundations set up around the world to carry out the Master’s wishes and decided it was about time I put myself on the line. The Who had set up a strong charitable trust of its own which appeased, to an extent, the feeling I had that Meher Baba would rather have seen me give to the poor than to the establishment of yet another so-called ‘spiritual center’.”

Pete Townshend also embarked on a project dedicated to the collection, restoration and maintenance of Meher Baba-related films. The project was known as MEFA, or Meher Baba European Film Archive.

Pete Townshend has been an active champion of children’s charities. The debut of Pete Townshend’s stage version of Tommy  took place at San Diego’s La Jolla Playhouse in July 1992. The show was earmarked as a benefit for the London-based Nordoff-Robbins Music Therapy Foundation, an organization which helps autistic and retarded children.

Pete Townshend performed at a 1995 benefit organized by Paul Simon at Madison Square Garden’s Paramount Theatre, for The Children’s Health Fund. The following year, Pete Townshend performed at a benefit for the Bridge School, a California facility for children with severe speech and physical impairments. In 1997, Pete Townshend established a relationship with Maryville Academy, a Chicago area children’s charity. Between 1997 and 2002, Pete Townshend played 5 benefit shows for Maryville Academy, raising at least $1,600,000. In addition, proceeds from the sales of his 1999 release Pete Townshend Live were also donated to Maryville Academy.

As a member of The Who, Pete Townshend has also performed a series of concerts, beginning in 2000, benefitting the Teenage Cancer Trust in the UK, raising several million pounds. In 2005, Pete Townshend performed at New York’s Gotham Hall for Samsung’s Four Seasons of Hope, an annual children’s charity fundraiser.

The Who rocker Pete Townshend is losing his hearing, and fears the disability will end his songwriting career. Pete Townshend blames his hearing loss on a lifetime spent using headphones, experts say today’s iPod Generation is storing up trouble for the future by listening to music at high volumes.

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Epilepsy Series-Disabled Legend George Fredrick Handel

George Frederick Handel was born on Friday 23 February 1685 and died on Saturday 14 April 1759. George was a German-born Baroque composer who is famous for his operas, oratorios and concerti grossi. Since the 1960s, with the revival of interest in baroque music, original instrument playing styles, and the prevalence of countertenors who could more accurately replicate castrato roles, interest has revived in Handel’s Italian operas, and many have been recorded and performed onstage.

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