Newton's laws of motion
Newton's laws of motion are three physical laws that, laid the foundation for classical mechanics. They describe the relationship between a body and the forces acting upon it, its motion in response to those forces. More the first law defines the force qualitatively, the second law offers a quantitative measure of the force, the third asserts that a single isolated force doesn't exist; these three laws have been expressed in several ways, over nearly three centuries, can be summarised as follows: The three laws of motion were first compiled by Isaac Newton in his Philosophiæ Naturalis Principia Mathematica, first published in 1687. Newton used them to investigate the motion of many physical objects and systems. For example, in the third volume of the text, Newton showed that these laws of motion, combined with his law of universal gravitation, explained Kepler's laws of planetary motion. A fourth law is also described in the bibliography, which states that forces add up like vectors, that is, that forces obey the principle of superposition.
Newton's laws are applied to objects which are idealised as single point masses, in the sense that the size and shape of the object's body are neglected to focus on its motion more easily. This can be done when the object is small compared to the distances involved in its analysis, or the deformation and rotation of the body are of no importance. In this way a planet can be idealised as a particle for analysis of its orbital motion around a star. In their original form, Newton's laws of motion are not adequate to characterise the motion of rigid bodies and deformable bodies. Leonhard Euler in 1750 introduced a generalisation of Newton's laws of motion for rigid bodies called Euler's laws of motion applied as well for deformable bodies assumed as a continuum. If a body is represented as an assemblage of discrete particles, each governed by Newton's laws of motion Euler's laws can be derived from Newton's laws. Euler's laws can, however, be taken as axioms describing the laws of motion for extended bodies, independently of any particle structure.
Newton's laws hold only with respect to a certain set of frames of reference called Newtonian or inertial reference frames. Some authors interpret the first law as defining. Other authors do treat the first law as a corollary of the second; the explicit concept of an inertial frame of reference was not developed until long after Newton's death. In the given interpretation mass, acceleration and force are assumed to be externally defined quantities; this is the most common, but not the only interpretation of the way one can consider the laws to be a definition of these quantities. Newtonian mechanics has been superseded by special relativity, but it is still useful as an approximation when the speeds involved are much slower than the speed of light; the first law states that if the net force is zero the velocity of the object is constant. Velocity is a vector quantity which expresses both the object's speed and the direction of its motion; the first law can be stated mathematically when the mass is a non-zero constant, as, ∑ F = 0 ⇔ d v d t = 0.
An object, at rest will stay at rest unless a force acts upon it. An object, in motion will not change its velocity unless a force acts upon it; this is known as uniform motion. An object continues to do. If it is at rest, it continues in a state of rest. If an object is moving, it continues to move without changing its speed; this is evident in space probes. Changes in motion must be imposed against the tendency of an object to retain its state of motion. In the absence of net forces, a moving object tends to move along a straight line path indefinitely. Newton placed the first law of motion to establish frames of reference for which the other laws are applicable; the first law of motion postulates the existence of at least one frame of reference called a Newtonian or inertial reference frame, relative to which the motion of a particle not subject to forces is a straight line at a constant speed. Newton's first law is referred to as the law of inertia. Thus, a condition necessary for the uniform motion of a particle relative to an inertial reference frame is that the total net force acting on it is zero.
In this sense, the first law can be restated as: In every material universe, the motion of a particle in a preferential reference frame Φ is determined by the action of forces whose total vanished for all times when and only when the velocity of the particle is constant in Φ. That is, a particle at rest or in uniform motion in the preferential frame Φ continues in that state unless compelled by forces to change it. Newton's first and second laws are valid only in an inertial reference frame. Any reference frame, in uniform motion with respect to an inertial frame is an in
Murphy's law is an adage or epigram, stated as: "Anything that can go wrong will go wrong". The perceived perversity of the universe has long been a subject of comment, precursors to the modern version of Murphy's law are not hard to find; the concept may be as old as humanity. Recent significant research in this area has been conducted by members of the American Dialect Society. Society member Stephen Goranson has found a version of the law, not yet generalized or bearing that name, in a report by Alfred Holt at an 1877 meeting of an engineering society, it is found that anything that can go wrong at sea does go wrong sooner or so it is not to be wondered that owners prefer the safe to the scientific.... Sufficient stress can hardly be laid on the advantages of simplicity; the human factor cannot be safely neglected in planning machinery. If attention is to be obtained, the engine must be such that the engineer will be disposed to attend to it. Mathematician Augustus De Morgan wrote on June 23, 1866: "The first experiment illustrates a truth of the theory, well confirmed by practice, what-ever can happen will happen if we make trials enough."
In publications "whatever can happen will happen" is termed "Murphy's law," which raises the possibility—if something went wrong—that "Murphy" is "De Morgan" misremembered. American Dialect Society member Bill Mullins has found a broader version of the aphorism in reference to stage magic; the British stage magician Nevil Maskelyne wrote in 1908: It is an experience common to all men to find that, on any special occasion, such as the production of a magical effect for the first time in public, everything that can go wrong will go wrong. Whether we must attribute this to the malignity of matter or to the total depravity of inanimate things, whether the exciting cause is hurry, worry, or what not, the fact remains. In 1948, humorist Paul Jennings coined the term resistentialism, a jocular play on resistance and existentialism, to describe "seemingly spiteful behavior manifested by inanimate objects", where objects that cause problems are said to exhibit a high degree of malice toward humans.
The contemporary form of Murphy's law goes back as far as 1952, as an epigraph to a mountaineering book by John Sack, who described it as an "ancient mountaineering adage": Anything that can go wrong, does. According to the book A History of Murphy's Law by author Nick T. Spark, differing recollections years by various participants make it impossible to pinpoint who first coined the saying Murphy's law; the law's name stems from an attempt to use new measurement devices developed by Edward Murphy. The phrase was coined in adverse reaction to something Murphy said when his devices failed to perform and was cast into its present form prior to a press conference some months — the first given by Dr. John Stapp, a U. S. Air Force colonel and Flight Surgeon in the 1950s; these conflicts were unreported until Spark researched the matter. His book expands upon and documents an original four part article published in 2003 on the controversy: Why Everything You Know About Murphy's Law is Wrong. From 1948 to 1949, Stapp headed research project MX981 at Muroc Army Air Field for the purpose of testing the human tolerance for g-forces during rapid deceleration.
The tests used a rocket sled mounted on a railroad track with a series of hydraulic brakes at the end. Initial tests used a humanoid crash test dummy strapped to a seat on the sled, but subsequent tests were performed by Stapp, at that time an Air Force captain. During the tests, questions were raised about the accuracy of the instrumentation used to measure the g-forces Captain Stapp was experiencing. Edward Murphy proposed using electronic strain gauges attached to the restraining clamps of Stapp's harness to measure the force exerted on them by his rapid deceleration. Murphy was engaged in supporting similar research using high speed centrifuges to generate g-forces. Murphy's assistant wired the harness, a trial was run using a chimpanzee; the sensors provided a zero reading. It was at this point that a disgusted Murphy made his pronouncement, despite being offered the time and chance to calibrate and test the sensor installation prior to the test proper, which he declined somewhat irritably, getting off on the wrong foot with the MX981 team.
In an interview conducted by Nick Spark, George Nichols, another engineer, present, stated that Murphy blamed the failure on his assistant after the failed test, saying, "If that guy has any way of making a mistake, he will." Nichols' account is that "Murphy's law" came about through conversation among the other members of the team. Others, including Edward Murphy's surviving son Robert Murphy, deny Nichols' account, claim that the phrase did originate with Edward Murphy. According to Robert Murphy's account, his father's statement was along the lines of "If there's more than one way to do a job, one of those ways will result in disaster he will do it that way." The phrase first received public attention during a press conference in which Stapp was asked how it was that nobody had been injured during the rocket sled tests. Stapp replied.
David Gerrold is an American science fiction screenwriter and novelist. He wrote the script for the original Star Trek episode "The Trouble with Tribbles", created the Sleestak race on the TV series Land of the Lost, wrote the novelette "The Martian Child", which won both Hugo and Nebula awards, was adapted into a 2007 film starring John Cusack. Gerrold was born Jerrold David Friedman to a Jewish family on January 1944 in Chicago, Illinois, he attended Van Nuys High School and graduated from Ulysses S. Grant High School in its first graduating class, Los Angeles Valley College, San Fernando Valley State College. Within days of seeing the Star Trek series premiere "The Man Trap" on 8 September 1966, 22-year-old Gerrold wrote a sixty-page outline for a two-part episode called "Tomorrow Was Yesterday", about the Enterprise discovering a ship launched from Earth centuries earlier. Although Star Trek producer Gene L. Coon rejected the outline, he realized Gerrold was talented and expressed interest in his submitting some story premises.
Bearing preliminary titles and, in some cases, preliminary character names, Gerrold submitted five premises. Two of the submissions of which he had little recollection involved a spaceship-destroying machine, similar to Norman Spinrad's "The Doomsday Machine", a situation in which Kirk had to play a chess game with an advanced intelligence using his crew as chess pieces. A third premise, "Bandi", involved a small being running about the Enterprise as someone's pet, which empathically sways the crew's feelings and emotions to comfort it at someone else's expense. A fourth premise, "The Protracted Man", applied science fiction to an effect seen in West Side Story, when Maria twirls in her dancing dress and the colours separate. Gerrold's story involved a man transported from a shuttlecraft trying out a new space warp technology; the man is no longer unified, separating into three visible forms when he moves, separated by a fraction of a second. As efforts are undertaken to correct the condition and move the Enterprise to where corrective action can be taken, the protraction worsens.
The fifth premise, "The Fuzzies", was initially rejected by Coon, but a while he changed his mind and called Gerrold's agent to accept it. Gerrold expanded the story to a full television story outline entitled "A Fuzzy Thing Happened To Me…", it became "The Trouble With Tribbles"; the name "Fuzzy" was changed because H. Beam Piper had written novels about a fictional alien species of the same name; the script went through numerous rewrites, including, at the insistence of Gerrold's agent, being re-set in a stock frontier town instead of an "expensive" space station. Gerrold wrote a book, The Trouble With Tribbles, telling the whole story about producing the episode and his earlier premises. "The Cloud Minders" from the third season has a story credited to Oliver Crawford. I came in with what I thought was a near-perfect Star Trek story, we find a culture that isn’t working for everybody and fix it, but my original ending was that, as they’re flying off, Kirk says, “Well, we solved another one.”
Spock says, “Well it’ll take years and years and years for all of these changes to be put in place.” And McCoy says, “I wonder how many children are going to die in the meantime.” So the idea was, “Let’s get gritty. We’re not going to change things overnight, but we can put changes in place that will have long-term effects.” There was more to the story, about the social issue, there was no magical zenite gas, causing the problem. Freddy Freiberger and Margaret Armen came in and changed it to a “Let’s solve it all in the last five minutes with gas masks”, and I thought, “That’s not a good story. It doesn’t do what Gene Roddenberry or Gene L. Coon would have been willing to do.” So I was disappointed. The Trouble with Tribbles was one of two books Gerrold wrote about Star Trek in the early 1970s after the original series had been canceled, his other was an analysis of the series, entitled The World of Star Trek, in which he criticized some of the elements of the show Kirk's habit of placing himself in dangerous situations and leading landing parties himself.
Gerrold contributed two stories for the Emmy Award-winning Star Trek: The Animated Series which ran from 1973 to 1974: "More Tribbles, More Troubles" and "Bem". "Bem" featured the first use of James T. Kirk's middle name, revealed to be Tiberius; this was entered into live-action canon in the movie Star Trek VI: The Undiscovered Country when Captain Kirk and Doctor McCoy are on trial for the death of the Klingon Chancellor Gorkon. Many of the changes Gerrold had advocated in The World of Star Trek were incorporated into Star Trek: The Next Generation when it debuted in 1987, he parted company with the producers at the beginning of the first season. Gerrold wrote a script for Star Trek: The Next Generation entitled "Blood and Fire", which included an AIDS metaphor and a gay couple in the ship's crew. Gerrold wrote this script in response to being with Roddenberry at a convention in 1987 where he had promised that the upcoming Next Generation series would deal with the issue of sexual orientation in the egalitarian future.
The script was purchased by the TNG producers, but shelved. He reworked the story into the third book in the Star Wolf series and again as a two-part episode of the fan-produced Star Trek: New Voyages, which he directed. Gerrold had wanted to appear onscreen in an episode of Star Trek "The Trouble with Tribbles"; the character of Ensign Freeman, who appears in the famous bar scene with the Klingons, was originall
The Universe is all of space and time and their contents, including planets, stars and all other forms of matter and energy. While the spatial size of the entire Universe is unknown, it is possible to measure the size of the observable universe, estimated to be 93 billion light years in diameter. In various multiverse hypotheses, a universe is one of many causally disconnected constituent parts of a larger multiverse, which itself comprises all of space and time and its contents; the earliest scientific models of the Universe were developed by ancient Greek and Indian philosophers and were geocentric, placing Earth at the center of the Universe. Over the centuries, more precise astronomical observations led Nicolaus Copernicus to develop the heliocentric model with the Sun at the center of the Solar System. In developing the law of universal gravitation, Isaac Newton built upon Copernicus' work as well as observations by Tycho Brahe and Johannes Kepler's laws of planetary motion. Further observational improvements led to the realization that the Sun is one of hundreds of billions of stars in the Milky Way, one of at least hundreds of billions of galaxies in the Universe.
Many of the stars in our galaxy have planets. At the largest scale galaxies are distributed uniformly and the same in all directions, meaning that the Universe has neither an edge nor a center. At smaller scales, galaxies are distributed in clusters and superclusters which form immense filaments and voids in space, creating a vast foam-like structure. Discoveries in the early 20th century have suggested that the Universe had a beginning and that space has been expanding since and is still expanding at an increasing rate; the Big Bang theory is the prevailing cosmological description of the development of the Universe. Under this theory and time emerged together 13.799±0.021 billion years ago and the energy and matter present have become less dense as the Universe expanded. After an initial accelerated expansion called the inflationary epoch at around 10−32 seconds, the separation of the four known fundamental forces, the Universe cooled and continued to expand, allowing the first subatomic particles and simple atoms to form.
Dark matter gathered forming a foam-like structure of filaments and voids under the influence of gravity. Giant clouds of hydrogen and helium were drawn to the places where dark matter was most dense, forming the first galaxies and everything else seen today, it is possible to see objects that are now further away than 13.799 billion light-years because space itself has expanded, it is still expanding today. This means that objects which are now up to 46.5 billion light-years away can still be seen in their distant past, because in the past when their light was emitted, they were much closer to the Earth. From studying the movement of galaxies, it has been discovered that the universe contains much more matter than is accounted for by visible objects; this unseen matter is known as dark matter. The ΛCDM model is the most accepted model of our universe, it suggests that about 69.2%±1.2% of the mass and energy in the universe is a cosmological constant, responsible for the current expansion of space, about 25.8%±1.1% is dark matter.
Ordinary matter is therefore only 4.9% of the physical universe. Stars and visible gas clouds only form about 6% of ordinary matter, or about 0.3% of the entire universe. There are many competing hypotheses about the ultimate fate of the universe and about what, if anything, preceded the Big Bang, while other physicists and philosophers refuse to speculate, doubting that information about prior states will be accessible; some physicists have suggested various multiverse hypotheses, in which our universe might be one among many universes that exist. The physical Universe is defined as all of their contents; such contents comprise all of energy in its various forms, including electromagnetic radiation and matter, therefore planets, stars and the contents of intergalactic space. The Universe includes the physical laws that influence energy and matter, such as conservation laws, classical mechanics, relativity; the Universe is defined as "the totality of existence", or everything that exists, everything that has existed, everything that will exist.
In fact, some philosophers and scientists support the inclusion of ideas and abstract concepts – such as mathematics and logic – in the definition of the Universe. The word universe may refer to concepts such as the cosmos, the world, nature; the word universe derives from the Old French word univers, which in turn derives from the Latin word universum. The Latin word was used by Cicero and Latin authors in many of the same senses as the modern English word is used. A term for "universe" among the ancient Greek philosophers from Pythagoras onwards was τὸ πᾶν, tò pân, defined as all matter and all space, τὸ ὅλον, tò hólon, which did not include the void. Another synonym was ho kósmos. Synonyms are found in Latin authors and survive in modern languages, e.g. the German words Das All and Natur for Universe. The same synonyms are found in English, such as everything, the cosmos, the world (as in the many-worlds interpr
Eric Frank Russell
Eric Frank Russell was a British author best known for his science fiction novels and short stories. Much of his work was first published in the United States, in John W. Campbell's Astounding Science Fiction and other pulp magazines. Russell wrote horror fiction for Weird Tales and non-fiction articles on Fortean topics. Up to 1955 several of his stories were published under pseudonyms, at least Duncan H. Munro and Niall Wilde. Russell was born in 1905 near Sandhurst in Berkshire, where his father was an instructor at the Royal Military College. Russell became a fan of science fiction and in 1934, while living near Liverpool, he saw a letter in Amazing Stories from Leslie J. Johnson, another reader from the same area. Russell met up with Johnson. Together, the two men wrote a novella, "Seeker of Tomorrow", published by F. Orlin Tremaine in the July 1937 number of Astounding Stories. Both Russell and Johnson became members of the British Interplanetary Society. Russell's first novel was Sinister Barrier, cover story for the inaugural, May 1939 issue of Unknown—Astounding's sister magazine devoted to fantasy.
It is explicitly a Fortean tale, based on Charles Fort's famous speculation "I think we're property", Russell explains in the foreword. An often-repeated legend has it that Campbell, on receiving the manuscript for Sinister Barrier, created Unknown as a vehicle for the short novel. There is no real evidence for it, despite a statement to that effect in the first volume of Isaac Asimov's autobiography, In Memory Yet Green, his second novel, Dreadful Sanctuary is an early example of conspiracy fiction, in which a paranoid delusion of global proportions is perpetuated by a small but powerful secret society. There are two different and mutually incompatible accounts of Russell's military service during World War II; the official, well-documented version is that he served with the Royal Air Force, with whom he saw active service in Europe as a member of a Mobile Signals Unit. However, in the introduction to the 1986 Del Rey Books edition of Russell's novel Wasp, Jack L. Chalker states that Russell was too old for active service, instead worked for Military Intelligence in London, where he "spent the war dreaming up nasty tricks to play against the Germans and Japanese", including Operation Mincemeat.
Russell's biographer John L. Ingham states however that "there is nothing nothing, in his R. A. F. record to show that he was anything more than a wireless mechanic and radio operator". Russell took up writing full-time in the late 1940s, he became an active member of British science fiction fandom and the British representative of the Fortean Society. He won the first annual Hugo Award for Best Short Story in 1955 recognizing his humorous "Allamagoosa" as the year's best science fiction; the 1962 novel The Great Explosion won a Prometheus Hall of Fame Award in 1985 — the third naming of two works to the libertarian science fiction hall of fame. The 1957 novel Wasp has been a finalist for the honor, now limited to one work per year; the Science Fiction and Fantasy Hall of Fame inducted Russell in 2000, its fifth class of two deceased and two living writers. Into Your Tent, a thorough and detailed biography of Russell by John L. Ingham, was published in 2010 by Plantech. Russell's full-length fiction includes the following: Sinister Barrier Dreadful Sanctuary Sentinels From Space, based on the earlier magazine story The Star Watchers Three to Conquer, based on the earlier magazine serial Call Him Dead Men and Machines, containing four related novellas Wasp Next of Kin, published earlier as The Space Willies The Great Explosion With a Strange Device published as The Mindwarpers.
Russell wrote a large number of shorter works, many of which have been reprinted in collections such as Deep Space, Six Worlds Yonder, Far Stars, Dark Tides and Somewhere a Voice. His short story "Allamagoosa", a science-fictional retelling of a traditional tall story called "The Shovewood", won the Hugo Award for Best Short Story. Russell wrote numerous non-fiction essays on Fortean themes, some of which were collected in a compendium of Forteana entitled Great World Mysteries, his second non-fiction book was The Rabble Rousers, a sardonic look at human folly including the Dreyfus affair and the Florida land boom. He wrote Lern Yerself Scouse: The ABZ of Scouse under the pseudonym "Linacre Lane". Two omnibus collections of Russell's science fiction are available from NESFA Press: Major Ingredients, containing 30 of his short stories, Entities containing five novels. John Pelan's Midnight House published Darker Tides, a collection of Russell's horror and weird fiction, in 2006; the 1995 novel Design for Great-Day, published as by Alan Dean Foster and Eric Frank Russell, is an expansion by Foster of a 1953 short story of the same name by Russell.
Russell had an easy-going, colloquial writing style, influenced in part by American "hard-boiled" detective fiction of the kind popularized by Black Mask magazine. Although British, Russell wrote predominantly for an American audience, was assumed to be American by readers. Much of Russell's science fiction is based on what might be described as Fortean themes, with Sinister Barrier and Dreadful Sanctuary the most notable examples. Another common theme is the single resourceful human pitted against a ponderous alien bureaucracy, as in the novels Wasp and Next of Kin, as well as several shorter works. Russell is sometimes categorized as a humorous writer, Brian Aldiss d