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Ballistic Coefficient
In ballistics, the ballistic coefficient (BC, ''C'') of a body is a measure of its ability to overcome air resistance in flight. It is inversely proportional to the negative acceleration: a high number indicates a low negative acceleration—the drag on the body is small in proportion to its mass. BC can be expressed with the units kilogram-force per square meter (kgf/m2) or pounds per square inch (lb/in2) (where 1 lb/in2 corresponds to ). Formulas General :C_\text = \frac = \frac where: *''C''b,physics, ballistic coefficient as used in physics and engineering *''m'', mass *''A'', cross-sectional area *''C''d, drag coefficient *\rho, density *\ell, characteristic body length Ballistics The formula for calculating the ballistic coefficient for small and large arms projectiles ''only'' is as follows: :C_\text = \frac where: *''C''b,projectile, ballistic coefficient as used in point mass trajectory from the Siacci method (less than 20 degrees). *''m'', mass of bullet *' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Five301906govtBullets
5Star (stylized as 5STAR) is a British free-to-air television channel owned by Channel 5 Broadcasting Limited, a wholly-owned subsidiary of Paramount Global, which is grouped under Paramount Networks UK & Australia division. It originally launched as the female-orientated Five Life on 15 October 2006, and was relaunched as Fiver on 28 April 2008 with a revised version of the same concept. The channel was later re-branded as 5* on 7 March 2011, and later, it was re-branded as its current name on 11 February 2016. The network focuses on documentaries, comedy and drama, with original content such as '' Rich Kids Go Skint'' and ''Young, Dumb & Banged Up in the Sun'', along with some American and Australian imports. History 2006-08: Five Life Five Life was intended to be a female-oriented channel emphasising lifestyle programming. Channel 5 announced that programming on launch would include ''The Ellen DeGeneres Show'', '' Love My Way'', '' Windfall'', '' Angela's Eyes'', and a week ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sir Isaac Newton
Sir Isaac Newton () was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author. Newton was a key figure in the Scientific Revolution and the Enlightenment that followed. His book (''Mathematical Principles of Natural Philosophy''), first published in 1687, achieved the first great unification in physics and established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for formulating infinitesimal calculus, though he developed calculus years before Leibniz. Newton contributed to and refined the scientific method, and his work is considered the most influential in bringing forth modern science. In the , Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. He used his mathematical description of gravity to deriv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordnance Ammunition
Ammunition, also known as ammo, is the material fired, scattered, dropped, or detonated from any weapon or weapon system. The term includes both expendable weapons (e.g., bombs, missiles, grenades, land mines), and the component parts of other weapons that create the effect on a target (e.g., bullets and warheads). The purpose of ammunition is to project a force against a selected target to have an effect (usually, but not always, lethal). An example of ammunition is the firearm cartridge, which includes all components required to deliver the weapon effect in a single package. Until the 20th century, black powder was the most common propellant used but has now been replaced in nearly all cases by modern compounds. Ammunition comes in a great range of sizes and types and is often designed to work only in specific weapons systems. However, there are internationally recognized standards for certain ammunition types (e.g., 5.56×45mm NATO) that enable their use across differe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gun Chronograph
A ballistic chronograph or gun chronograph is a measuring instrument used to measure the velocity of a projectile in flight, typically fired from a gun or other firearm. The instrument is often useful for tasks such as gauging the utility of a firearm or safety of less-lethal projectiles fired from items such as a paintball gun or BB gun. History Benjamin Robins (1707–1751) invented the ballistic pendulum that measures the momentum of the projectile fired by a gun. Dividing the momentum by the projectile mass gives the velocity. Robbins published his results as ''New Principles of Gunnery'' in 1742. The ballistic pendulum could make only one measurement per firing because the device catches the projectile. The gun's accuracy also limited how far down range a measurement could be made. Alessandro Vittorio Papacino d'Antoni published results in 1765 using a wheel chronometer. This used a horizontal spinning wheel with a vertical paper mounted on the rim. The bullet was fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leonhard Euler
Leonhard Euler ( ; ; ; 15 April 170718 September 1783) was a Swiss polymath who was active as a mathematician, physicist, astronomer, logician, geographer, and engineer. He founded the studies of graph theory and topology and made influential discoveries in many other branches of mathematics, such as analytic number theory, complex analysis, and infinitesimal calculus. He also introduced much of modern mathematical terminology and Mathematical notation, notation, including the notion of a mathematical function. He is known for his work in mechanics, fluid dynamics, optics, astronomy, and music theory. Euler has been called a "universal genius" who "was fully equipped with almost unlimited powers of imagination, intellectual gifts and extraordinary memory". He spent most of his adult life in Saint Petersburg, Russia, and in Berlin, then the capital of Kingdom of Prussia, Prussia. Euler is credited for popularizing the Greek letter \pi (lowercase Pi (letter), pi) to denote Pi, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Speed Of Sound
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elasticity (solid mechanics), elastic medium. More simply, the speed of sound is how fast vibrations travel. At , the speed of sound in air is about , or in or one mile in . It depends strongly on temperature as well as the medium through which a sound wave is propagating. At , the speed of sound in dry air (sea level 14.7 psi) is about . The speed of sound in an ideal gas depends only on its temperature and composition. The speed has a weak dependence on frequency and pressure in dry air, deviating slightly from ideal behavior. In colloquial speech, ''speed of sound'' refers to the speed of sound waves in Earth's atmosphere, air. However, the speed of sound varies from substance to substance: typically, sound travels most slowly in gases, faster in liquids, and fastest in solids. For example, while sound travels at in air, it travels at in water (almost 4.3 times a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euler Method
In mathematics and computational science, the Euler method (also called the forward Euler method) is a first-order numerical analysis, numerical procedure for solving ordinary differential equations (ODEs) with a given Initial value problem, initial value. It is the most basic explicit and implicit methods, explicit method for numerical ordinary differential equations, numerical integration of ordinary differential equations and is the simplest Runge–Kutta method. The Euler method is named after Leonhard Euler, who first proposed it in his book ''Institutionum calculi integralis'' (published 1768–1770). The Euler method is a first-order method, which means that the local error (error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size. The Euler method often serves as the basis to construct more complex methods, e.g., predictor–corrector method. Geometrical description Purpose and why i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ballistic Pendulum
A ballistic pendulum is a device for measuring a bullet's momentum, from which it is possible to calculate the velocity and kinetic energy. Ballistic pendulums have been largely rendered obsolete by modern chronographs, which allow direct measurement of the projectile velocity. Although the ballistic pendulum is considered obsolete, it remained in use for a significant length of time and led to great advances in the science of ballistics. The ballistic pendulum is still found in physics classrooms today, because of its simplicity and usefulness in demonstrating properties of momentum and energy. Unlike other methods of measuring the speed of a bullet, the basic calculations for a ballistic pendulum do not require any measurement of time, but rely only on measures of mass and distance. In addition its primary uses of measuring the velocity of a projectile or the recoil of a gun, the ballistic pendulum can be used to measure any transfer of momentum. For example, a ballistic pendul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benjamin Robins
Benjamin Robins (170729 July 1751) was a pioneering British scientist, Newtonian mathematician, and military engineer. He wrote an influential treatise on gunnery, for the first time introducing Newtonian science to military men, was an early enthusiast for rifled gun barrels, and his work had substantive influence on the development of artillery during the latter half of the eighteenth century – and directly stimulated the teaching of calculus in military academies. Early life Benjamin Robins was born in Bath. His parents were Quakers in poor circumstances, and as a result, he received very little formal education. Having come to London on the advice of Dr. Henry Pemberton (1694–1771), who had recognised Robins's talents, for a time he maintained himself by teaching mathematics, but soon devoted himself to engineering and the study of fortification. Scientific gunnery In particular he carried out an extensive series of experiments in gunnery, embodying his results in his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bernoulli Differential Equation
In mathematics, an ordinary differential equation is called a Bernoulli differential equation if it is of the form : y'+ P(x)y = Q(x)y^n, where n is a real number. Some authors allow any real n, whereas others require that n not be 0 or 1. The equation was first discussed in a work of 1695 by Jacob Bernoulli, after whom it is named. The earliest solution, however, was offered by Gottfried Leibniz, who published his result in the same year and whose method is the one still used today. Bernoulli equations are special because they are nonlinear differential equations with known exact solutions. A notable special case of the Bernoulli equation is the logistic differential equation. Transformation to a linear differential equation When n = 0, the differential equation is linear. When n = 1, it is separable. In these cases, standard techniques for solving equations of those forms can be applied. For n \neq 0 and n \neq 1, the substitution u = y^ reduces any Bernoulli equatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johann Bernoulli
Johann Bernoulli (also known as Jean in French or John in English; – 1 January 1748) was a Swiss people, Swiss mathematician and was one of the many prominent mathematicians in the Bernoulli family. He is known for his contributions to infinitesimal calculus and educating Leonhard Euler in the pupil's youth. Biography Early life Johann was born in Basel, the son of Nicolaus Bernoulli, an apothecary, and his wife, Margarethe Schongauer, and began studying medicine at University of Basel. His father desired that he study business so that he might take over the family spice trade, but Johann Bernoulli did not like business and convinced his father to allow him to study medicine instead. Johann Bernoulli began studying mathematics on the side with his older brother Jacob Bernoulli. Throughout Johann Bernoulli's education at Basel University, the Bernoulli brothers worked together, spending much of their time studying the newly discovered infinitesimal calculus. They were among t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Velocity
Velocity is a measurement of speed in a certain direction of motion. It is a fundamental concept in kinematics, the branch of classical mechanics that describes the motion of physical objects. Velocity is a vector (geometry), vector Physical quantity, quantity, meaning that both magnitude and direction are needed to define it. The Scalar (physics), scalar absolute value (Magnitude (mathematics), magnitude) of velocity is called , being a coherent derived unit whose quantity is measured in the International System of Units, SI (metric system) as metres per second (m/s or m⋅s−1). For example, "5 metres per second" is a scalar, whereas "5 metres per second east" is a vector. If there is a change in speed, direction or both, then the object is said to be undergoing an ''acceleration''. Definition Average velocity The average velocity of an object over a period of time is its Displacement (geometry), change in position, \Delta s, divided by the duration of the period, \Delt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
