Captain Nemo and Professor Aronnax contemplating measuring instruments in Twenty Thousand Leagues Under the Sea

In physics and engineering, measurement is the activity of comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the measurement results in a given number for the relationship between the item under study and the referenced unit of measurement. Measuring instruments are the means by which this translation is made. All measuring instruments are subject to varying degrees of instrument error. Download high resolution version (517x721, 153 KB) Wikipedia does not have an article with this exact name. ... Download high resolution version (517x721, 153 KB) Wikipedia does not have an article with this exact name. ... Captain Nemos first appearance This page is about the fictional character Captain Nemo. ... Front page of Vingt mille lieues sous les mers 20,000 Leagues Under the Seas (or Twenty Thousand Leagues Under the Seas) is a classic science fiction novel by Jules Verne (1828–1905), published in 1870 under the title Vingt mille lieues sous les mers. ... A Superconductor demonstrating the Meissner Effect Physics (from the Greek, φυσικός (physikos), natural, and φύσις (physis), nature) is the science of the natural world dealing with the fundamental constituents of the universe, the forces they exert on one another, and the results produced by these forces. ... Engineering applies scientific and technical knowledge to solve human problems. ... Various meters In classical physics and engineering, measurement generally refers to the process of estimating or determining the ratio of a magnitude of a quantitative property or relation to a unit of the same type of quantitative property or relation. ... A physical quantity is either a quantity within physics that can be measured (e. ... In philosophy, an object is a thing, an entity, or a being. ... An event is something that takes place; an occurrence and arbitrary point in time. ... The word unit means any of several things: Unit of measurement, a fundamental quantity of measurement Units (computer program), a popular program that does unit conversion Units conversion by the Factor-label method Functional unit, a component of a computer system such as the CPU Unit of action, a discrete... Instrument error refers to the combined accuracy and precision of a measuring instrument, or the difference between the actual value and the value indicated by the instrument (error). ...

Physicists use a vast range of instruments to perform their measurements. These range from simple objects such as rulers and stopwatches to electron microscopes and particle accelerators. Virtual instrumentation is widely used in the development of modern measuring instruments. It has been suggested that Selected area diffraction be merged into this article or section. ... A 1960s single stage 2MeV linear Van de Graaff accelerator, here opened for maintenance A particle accelerator is a device that uses electric and/or magnetic fields to propel electrically charged particles to high speeds. ... Virtual Instrumentation is the use of customizable software and modular measurement hardware to create user-defined measurement systems, called virtual instruments. ...

• Mass
  • balance
  • weighing scales
  • mass spectrometer
  • katharometer

History of weights and measures

• Time
  • calendar
  • chronometer
  • clock
  • atomic clock
  • radiometric dating

Timeline of time measurement technology

• Length (i.e., distance)
  • altimeter (measures height)
  • architect's scale
  • engineer's scale
  • interferometer
  • micrometer
  • pi tape
  • odometer
  • opisometer
  • ruler
  • tape measure
  • laser rangefinder
  • ultrasound distance measure
  • GPS
  • Electronic distance meter

• Area
  • planimeter

• Angles
  • sextant
  • theodolite
  • protractor

• Temperature
  • thermometer
  • thermocouples
  • thermistors
  • pyrometers
  • electromagnetic spectroscopy

• Humidity
  • hygrometer

• Pressure
  • barometer
  • manometer
  • Pitot tube (used to determine speed)
  • anemometer (used to determine wind speed)
  • tire-pressure gauge

• Flow

• pH

• Level
  • spirit level
  • laser line level
  • Dumpy level
  • Tiltmeter

• Radiation
  • geiger counter
  • Nichols radiometer

• Sound

• Light
  • Photometer
  • Spectrometer

• Speed
  • speedometer
  • airspeed indicator

• Torque
  • De Prony brake

• Electrical properties
  • electrometer (measures charge)
  • ammeter (measures electrical current)
  • galvanometer (measures current)
  • ohmmeter (measures resistance)
  • voltmeter (measures voltage)
  • Wheatstone bridge
  • multimeter (measures all of the above)
  • oscilloscope
  • watt meter (measures power)
  • electric energy meter (measures energy)

• Hardness
  • durometer

• Density
  • Pycnometer

• Uncategorized
  • colorimeter (measures absorbance, and thus concentration)
  • radiometry
  • sicroscope
  • spectroscopy is an important tool used by physicists.

Mass is a property of a physical object that quantifies the amount of matter it contains. ... For other meanings of the word balance, see: propaganda equilibrium (disambiguation page) sense of balance weighing scale analytical balance (a precise weighing scale) balance beam in gymnastics Balance (song) homeostasis, the biological balance within a human or other animals body When the weights on the plates of this balance... A doctors scale A weighing scale (usually just scale in common usage) is a device for measuring the weight of an object. ... Mass spectrometry is a technique for separating ions by their mass-to-charge (m/z) ratios. ... A katharometer is an instrument for determining the composition of a gas mixture. ... The definition, agreement and practical use of units of weights and measures have played a crucial role in human endeavor from early ages up to this day. ... Watches are used to measure time Trying to understand time has long been a prime occupation for philosophers, scientists and artists. ... A calendar is a system for naming periods of time, typically days. ... A chronometer is a clock accurate enough to be used as a portable time standard on a vehicle, usually in order to determine longitude by means of celestial navigation. ... A wall clock A clock (from the Latin cloca, bell) is an instrument for measuring time. ... Atomic clock Chip-Scale Atomic Clock Unveiled by NIST An atomic clock is a type of clock that uses an atomic resonance frequency standard as its counter. ... Radiometric dating is a technique used to date materials based on a knowledge of the decay rates of naturally occurring isotopes, and the current abundances. ... Timeline of time measurement technology 270 BC - Ctesibius builds a popular water clock 46 BC - Julius Caesar and Sosigenes develop a solar calendar with leap years 1000s - Sets of hourglasses were maintained by ships pages to mark the progress of a ship during its voyage 1000s - Large town clocks... In general English usage, length (symbols: l, L) is but one particular instance of distance – an objects length is how long the object is – but in the physical sciences and engineering, the word length is in some contexts used synonymously with distance. Height is vertical distance; width (or breadth... Aircraft altimeter as used in North America An altimeter is an active instrument used to measure the altitude of an object above a fixed level. ... An architects scale is a specialized ruler. ... An engineers scale is a ruler, a tool for measuring distances. ... Interferometry is the applied science of combining two or more input points of a particular data type, such as optical measurements, to form a greater picture based on the combination of the two sources. ... External, internal, and depth micrometers A micrometer is a widely used device in mechanical engineering for precisely measuring thickness of blocks, outer and inner diameters of shafts and depths of slots. ... An odometer is a device used for indicating distance traveled by an automobile or other vehicle. ... An opisometer or map measurer is an instrument for measuring the lengths of arbitrary curved lines. ... A ruler is an instrument used in geometry and technical drawing to measure short distances and/or to rule straight lines. ... Self-retracting pocket tape measure A tape measure or measuring tape is a ribbon of cloth, plastic, or metal with linear-measure markings, often in both imperial and metric units. ... Soon after the invention of the laser in 1960, it was described as a solution in search of a problem. However, since that time, the laser has found a place as a useful tool in many scientific, military, medical and industrial applications. ... Over fifty GPS satellites such as this NAVSTAR have been launched since 1978. ... Area is a physical quantity expressing the size of a part of a surface. ... Planimeter A planimeter is a technical drawing instrument used to measure the surface area of an arbitrary two dimensional shape. ... This article is about angles in geometry. ... For other uses, see Sextant (disambiguation). ... Diagram of an Optical Theodolite. ... A protractor is a semicircular tool for measuring angles. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... A thermometer is a device which measures temperature or temperature gradient, using a variety of different principles. ... In electronics, thermocouples are a widely used type of temperature sensor and can also be used as a means to convert thermal energy into electrical energy. ... A thermistor is a type of resistor used to measure temperature changes, relying on the change in its resistance with changing temperature. ... A pyrometer is a non-contact temperature measuring device, generally the term is applied to instruments measuring temperatures above 600 degrees Celsius. ... Electromagnetic spectroscopy a. ... Humidity is the concentration of water vapor in the air. ... A sling psychrometer for outdoor use The interior of a Stevenson screen showing a motorized psychrometer A interior of a simple indoor hygrometer. ... Pressure(symbol: p) is the forceper unit areaacting on a surface in a direction perpendicularto that surface. ... Schematic drawing of a simple mercury barometer with vertical mercury column and reservoir at base A barometer is an instrument used to measure atmospheric pressure. ... A manometer is a pressure measuring instrument, often also called pressure gauge. ... A Pitot tube is a measuring instrument used to measure fluid flow. ... Speed (symbol: v) is the rate of motion, or equivalently the rate of change of position, expressed as distance d moved per unit of time t. ... Anemometer installation on roof of Deconism Gallery, using three size 6, schedule 40 pipes in their original uncut 20 foot (6 m) lengths. ... Speed (symbol: v) is the rate of motion, or equivalently the rate of change of position, expressed as distance d moved per unit of time t. ... A tire pressure gauge is used to measure the pressure of tires on a vehicle. ... In fluid dynamics, the rate of fluid flow is the volume of fluid which passes through a given area per unit time. ... The correct title of this article is pH. The initial letter is capitalized due to technical restrictions. ... Level has more than one meaning. ... A spirit level is an instrument designed to indicate whether a surface is level. ... Typical consumer laser line level using spirit levels for three planes and including a digital stud sensor display. ... also known as a transit level. ... A tiltmeter is a device used to measure the slope, or tilt, of the Earths surface. ... Radiation has a variety of different meanings. ... Image:A Geiger counter. ... A Nichols radiometer is the apparatus used by Nichols and Hull in 1901 for the measurement of radiation pressure. ... A schematic representation of hearing. ... Prism splitting light Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific context, electromagnetic radiation of any wavelength. ... In the broadest sense, a photometer is any instrument used to measure illuminance or irradiance. ... A spectrometer is an optical instrument used to measure properties of light over a specific portion of the electromagnetic spectrum. ... Speed (symbol: v) is the rate of motion, or equivalently the rate of change of position, expressed as distance d moved per unit of time t. ... Speedometer gauge on a car, showing the speed of the vehicle in miles and kilometre per hour on the out– and inside respectively. ... Airspeed Indicator The airspeed indicator is an instrument used in an aircraft to display the crafts airspeed, typically in knots, to the pilot. ... In physics, torque can be thought of informally as rotational force. Torque is commonly measured in units of newton metres; although, centiNewton Meters (cNm), Foot Pounds (Lb-Ft), Inch Pounds (Lb-In) and Inch Ounces (Oz-In) are also frequently used expressions of torque. ... An electrometer is an electrical instrument for measuring electric charge or electrical potential difference. ... Wire carrying current to be measured Spring providing restoring force An ammeter is a measuring instrument used to measure the flow of electric current in a circuit. ... It has been suggested that Tangent galvanometer be merged into this article or section. ... An Ohmmeter is an electrical measuring instrument that measures electrical resistance, the opposition to the flow of an electric current. ... Two digital voltmeters A voltmeter is a measuring instrument for measuring the voltage between two points in an electric circuit. ... A Wheatstone bridge is a measuring instrument invented by Samuel Hunter Christie in 1833 and improved and popularized by Sir Charles Wheatstone in 1843. ... howard piA digital multimeter A low cost digital multimeter An analog multimeter A multimeter is an electronic measuring instrument that combines several functions in one unit. ... A Tektronix model 475A portable analogue oscilloscope, a very typical instrument of the late 1970s. ... The wattmeter is an electrodynamic instrument for measuring the electric power or the supply rate of electrical energy of any given circuit. ... Typical US domestic electricity meter An electricity meter is generally taken to be a device which measures the amount of electrical energy supplied to a customer of an electricity company. ... A durometer is a tool used to measure hardness. ... Density (symbol: ρ - Greek: rho) is a measure of mass per unit of volume. ... The pycnometer or pyknometer is a device used for measuring fluid density, also known as a specific gravity bottle. ... A colorimeter is generally any tool that characterizes colour samples to provide an objective measure of colour characteristics. ... In spectroscopy, the absorbance A is defined as , where I is the intensity of light at a specified wavelength λ that has passed through a sample (transmitted light intensity) and is the intensity of the light before it enters the sample (or incident light intensity). ... In chemistry, concentration is the measure of how much of a given substance there is mixed with another substance. ... In telecommunication and physics, radiometry is the science of radiation measurement. ... Extremely high resolution spectrum of the Sun showing thousands of elemental absorption lines (fraunhofer lines) Spectroscopy is the study of spectra, that is, the dependence of physical quantities on frequency. ... A modern hammer is directly descended from ancient hand tools A tool is a device that (most commonly) provides a mechanical advantage in accomplishing a physical task. ...

See also

Timeline of temperature and pressure measurement technology Timeline of temperature and pressure measurement technology 1592 - Galileo Galilei builds a crude thermometer using the contraction of air to draw water up a tube 1612 - Santorre Santorio puts thermometer to medical use 1643 - Evangelista Torricelli invents the mercury barometer 1714 - Daniel Gabriel Fahrenheit invents the mercury in glass thermometer...