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| binding energy
— net energy that must be supplied to overcome the strong nuclear force in order to split an atomic nucleus into its constituent particles. biomechanics — study of the motion of various parts of the human body (or other living organisms). black hole — gravitational singularity predicted by general relativity. blackbody — absorbs 100% of the electromagnetic radiation (i.e., thermal radiation) incident upon its surface. block and tackle — system of pulleys that changes the magnitude of the input force, not just its direction. Often used in sailing. Bohr model — model of the hydrogen atom, proposed by Danish physicist Niels Bohr, where the electron moves in circular orbits only at discrete or quantized radii from the nucleus. Boltzmann’s constant — constant describing the conversion between microscopic thermal energy per particle and macroscopic temperature. The value of Boltzmann’s constant is kB = 1.38×10−23 J/K. Boyle’s law — for a gas at constant temperature, the change in pressure is inversely proportional to the change in volume. Often written P1V1 = P2V2. brittle — material property describing the tendency to break before deforming. Brittle is the opposite of elastic. Brownian motion — random, jerky movement of extremely small particles floating in still water observed by Robert Brown in 1827. Calorie — unit of heat energy equal to 1,000 calories or 4,180 J. The Calorie, written with a capital “C” and typically used to list the energy content in foods, should not be confused with the calorie that is written with a lowercase “c.” calorie — unit of heat energy corresponding to the quantity of heat required to increase the temperature of 1 g of water by 1°C, or 4.18 J. The calorie is written with a lowercase “c” and is not to be confused with the capital “C” unit of the Calorie, which is equal to 1,000 calories. | capacitance
— measure of the ability of a capacitor (or other conductor) to store electric charge.
The unit of capacitance is the farad (F), although it is also measured in coulombs per volt (C/V). capacitor — device with two parallel conducting plates separated by a narrow gap usually filled with an insulating material. A capacitor is a device that stores electric charge. carbon dating — procedure for determining the time since death or age of an organic material by measuring the fraction of the radioactive isotope carbon-14. Carnot cycle — four-stage process of an idealized heat engine, consisting of: (1) adding heat during isothermal expansion; (2) adiabatic expansion; (3) rejecting heat during isothermal compression; and (4) adiabatic compression. Carnot efficiency — ideal maximum percentage of the input energy that can be converted into work by a heat engine. Cartesian coordinates — coordinate system in which positions are specified with coordinate values along two or three perpendicular axes labeled x, y, and z. cathode ray tube (CRT) — vacuum tube in which a cathode emits a beam of electrons that are deflected by magnetic fields before hitting a phosphorescent screen. By suitably controlling the signal in the electromagnets, an image can be created on the screen. Celsius scale — relative temperature scale where 0°C is defined as the temperature that water freezes and 100°C is the temperature that water boils. center of mass — average position of all the mass in an object. The center of mass is the point around which the object balances in any direction. centripetal acceleration — any acceleration perpendicular to an object’s velocity that causes it to move in a circle. The centripetal acceleration is directed towards the center of the circle. centripetal force — any force perpendicular to an object’s velocity that causes it to move in a circle. The centripetal force is directed towards the center of the circle. | |||||||||||||
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