List of Important elements and terms related to Physics (science) with it’s definition and explanation

List of Important elements and terms related to Physics (science) with it’s definition and explanation.

• Acceleration: It is the rate of change of the velocity of a moving body.

• Acoustics: It is the experimental and theoretical science of sound and its transmission.

• Alternative energy: It is the energy from sources that are renewable and ecological safe, as opposed to sources

that are non-renewable with toxic by-product, such as coal, oil or gas and uranium.

• Altimeter: It is an instrument used in aircraft that measures altitude, or height above sea level.

• Ammeter: It is a device used to measure current.

• Archimedes principle: It is the law stating that an object that is totally or partly submerged in a fluid displaces a

volume of fluid that weighs the same as the apparent loss in weight of the object.

• Armature: It is a part of some electric machines.

• Atmosphere: It is the mixture of gases that surrounds the Earth; it is prevented from escaping by the pull of the

Earth’s gravity.

• Atom: It is the smallest unit of matter that can take part in a chemical reaction and which cannot be broken down

chemically into anything simpler.

• Astrophysics: It is the study of the structure of the universe and how the objects in it behave.

• Ballistics: It is the science of the movement and behaviour of missiles. Projectiles from guns, refuels and slings,

bombs, rockets and so forth.

• Barometer: It is the instrument that measures atmospheric pressure as indication weather.

• Buoyancy: It is the effect of the upward force (upthrust) on an objective in a fluid.

• Calibrate: It describes how a measuring scale is marked.

• Calliper: It is a kind of measuring instrument.

• Calorie: It is a unit of energy content of food.

• Calorimeter: It is an apparatus for measuring heat.

• Cantilever: It is a beam securely fixed at one end and hanging fee at the other hand.

• Capacitor: It is a device which can store electricity.

• Capillarity: It is an effect of surface tension.

• Carat: It is a unit of weight for gems and precious metals. One carat is equal to 200 milligrams.

• Cathode: It is a negative electrode in a cell.

• Celsius: The temperature scale in which one division or degree is taken as one hundredth part of the interval

between the freezing point (00C) and the boiling point (1000 C) of water at standard atmospheric pressure.

• Centrifugal: It is a force away from the centre that may appear to be observed during motion in a curve.

• Centripetal: It is the force that is necessary to keep an object moving in a circular path and that is directed

inwards towards the centre of rotation.

• Chain reaction: It is a situation where one event cause a second, this leads to a third, and so on.

• Circuit breaker: It is a safety switch that automatically cuts off the current when there is an overland.

• Climate: It is the long-term pattern of weather in a region.

• Compass: it is an instrument which helps people to find their way from one place to another.

• Cooling tower: It is part of a power station.

• Coulomb: It is a unit of electric charge.

• Cube: It has a solid shape, it has six square sides which are all the same size.

• Curie: It is a unit of radio-activity.

• Decibel: It is a unit of measurement. It measures the loudness of sound.

• Diffusion: It is the movement of atoms and molecules in gases and liquids.

• Digital: It is a term meaning coded as number.

• Diode: It is a term part of some electric circuits.

• Docking: It is the mechanical coupling of two or more spacecraft.

• Dynamo: It is a simple generator, or machine for transforming mechanical energy into electrical energy.

• Echo: It is a sound which is reflected.

• Eclipse: it is passage of an astronomical body through the shadow of another.

• Electromagnet: It is a special coil of wire.

• Element: It is substance that cannot be split chemically into simpler substances.

• Elastically: It is an elastic substance which obey Hooke’s law. This means that if we stretch or compress a

sample, it deforms (stains) in proportion. It returns to its original state when the stress ceases.

• Electron: It is one of the basic particles of matter.

• Epicentre: It is a point directly above the true centre of disturbing from which the shock wavers of an earthquakes

apparently radiate.

• Escape speed: It is the speed of an object leaving the surface of a planet, such that it just escapes the

gravitational pull.

• Escape velocity: It is the minimum velocity with which an object must be projected for it to escape from the

gravitational pull of a planetary body.

• Fallout: These are the radio-active substance deposited upon the surface of the earth after the explosion of a

nuclear weapon of mishap at a nuclear reactor.

• Fibre optics: It is branch of physics dealing with the transmission of light and images though glass or plastic

known as optical fibres.

• Filament: It is a thin, high resistance wire as in an electric light bulb.

• Filter: It is a kind of apparatus which helps to separate a mixture.

• Fleming’s rules: These are memory aids for the directions of the magnetic field, current and motion in an electric

generator or motor, using one’s fingers.

• Fly wheel: It is a heavy wheels connected to the shaft of an engine. it maintains the smooth rotation of the shaft

because of its high inertia.

• Forensic science: It carries out test and searches for clues to help the police and lawyers.

• Fossil fuel: Any fuel produced by the slow decay of dead things and which, therefore, is not renewable.

• Free fall: It is the state in which a body is falling freely under the influence of gravity, as in free-fall parachuting.

• Friction: It is the force that opposes the relative motion of two bodies in contact.

• Fuse: It is a thin piece of wire, a part of an electric circuit.

• Galvanometer: It is a sensitive instrument for detecting or measuring small electric currents.

• Gas: It is a state of matter which has no fixed shape or volume and always fills the whole of the space in which it

is contained.

• Geiger counter: It is a device which measures radiation.

• Generator: It is a machine that transfers kinetic energy to electricity.

• Greenhouse effect: It is a phenomenon of the Earth’s atmosphere by which solar radiation, absorbed by the Earth

and re-emitted from the surface, is prevented from escaping by gases, mainly carbon dioxide in the air.

• Grid: It is the network by which electricity is generated and distributed over a region or country.

• Hectare: It is a unit of measurement which measures area.

• Hertz: It is a unit of measurement which measures the frequency of vibrations.

• Hexagon: It is a flat shape which has six sides.

• Horse power (hp): It is a practical unit of power which equal to 550 foot-pound per second or 746 watts.

• Hurricane: It is a powerful whirling tropical storm that measures 320 to 480 kilometres in diameter.

• Hydraulics: It is the branch of physics that deals with the behaviour of liquids at rest and in motion.

• Hydrometer: It is an instrument used to measures the relatives density of liquids (the density compared with that

of water).

• Hydrosphere: The water of the earth, ocean lakes, rivers and glaciers that cover about three-fourths of the earth’s

surface.

• Hygrometer: It is an instrument used to measure the amount of water vapour in the air.

• Hypersonic: The sound waves which have frequencies above 500 megahertz.

• Hypersonic speed: The speed of an object greater than about five times the speed of sound in the fluid through

which the object is moving.

• Inertia: The tendency of an object to remain in a state of rest of uniform motion until an external force is applied,

as stated by Newton’s first law of motion.

• Information Technology: It is a scientific subject, the study of how to collect, use, move, store and display

information.

• Insulation: It is the process by which the passage of electricity, heat or sound is prevented through a material.

• Imaging: It is a technique by which electronics data collected by various means is converted into visual image by

use of computers.

• Isotopes: These are atoms of an element having the same atomic number but different atomic weights.

• Jet lag: It is a state of feeling unwell and exhausted experienced by air travellers when they cross several time

zones in a relatively short time.

• Kinetic energy: It is a form of energy possessed by moving bodies. It is contrasted with potential energy.

• Knot: It is a unit for measuring ship’s speed.

• Laser: The name stands for Light Amplification by stimulated Emission of Radiation. A device able to produce an

intension narrow beam of radiation.

• Latent heat: It is the heat required to change the state of a substance (for example, from solid to liquid) without

changing its temperature.

• Latitude: It is the distance of a point on the earth’s surface from the equator.

• Lighting conductor: It is a conductor of electricity installed in a structure to save it from damage.

• Light-year: It is a unit of distance used in astronomy. It is defined as the distance light travels through space in

one year. Light travels at 300,000 km per second.

• Mach number: It is a measure of the speed of an object, specially an aircraft. If the Mach number exceeds one,

the object is said to be moving at a supersonic speed.

• Manometer: An instrument for measuring the pressure of liquids (including human blood pressure) or gases.

• Mechanics: It is the study of movement of material bodies.

• Meridian: It is an imaginary circle passing through both the poles of a celestial sphere, It is also the imaginary

plane passing through the Earth’s axis.

• Meteorology: It is the study of climate and weather patterns, with the aim of trying to explain, predict and change

them.

• Mica: It is a group of silicate minerals having layered structure.

• Microscope: It is an instrument for magnification with high resolution for detail.

• Mirage: It is the illusion seen in hot climate of water on the horizon, or of distant objects being enlarged.

• Missile: It is guided unmanned weapon which is usually propelled by a rocked.

• Moderator: It is a substance that is used to slow down neutrons emitted in a nuclear fission reaction.

• Molecule: it is a group of one or more atoms bonded together, a basic participle of matter.

• Momentum: It is a property dependent on the mass and velocity of a body.

• Nautical mile: It is a unit of measurement, it measures distances across seas and oceans.

• Nuclear fission: it is the process whereby an atomic nucleus breaks up with the emissions of several neutrons.

• Nuclear reactor: It is the central component of a nuclear power station that generated nuclear energy under

controlled conditions for use as a source of electrical power.

• Nuclear waste: It is the radio-active and toxic by-products of the nuclear-energy and nuclear-weapons industries.

• Ohm: The SI unit of electrical resistance, named after Georg Simon Ohm.

• Opaque: It described a substance which does not allow light to pass through it.

• Optics: It is the study of nature and properties of light.

• Oscillation: One completer to and-fro movement of a vibrating object or system.

• Periscope: It is an optical instrument designed for observation from a concealed position such as from a

submerged submarine.

• Photon: It is a particle which has been invented by scientist to explain how light behaves.

• Physics: It is the branch of science concerned with the ultimate laws that govern the structure of the universe and

the forms of matter and energy and their interactions.

• Piston: It is a part of a machine, it is fitted inside a cylinder and moves back wards and forwards.

• Plutonium: It is a radioactive metallic element (symbol Pu) of proton number 94 and relative atomic mass 239.13.

• Pole: It is a region of a magnetic field where the force is strongest. Most bar magnets have two poles.

• Pollution: The effect on the surface of the Earth of poisonous or harmful substances that makes life less safe or

pleasant for living organisms.

• Potential energy: It is stored energy.

• Primary colour: A primary colour is one of there different colours of light red. Green and blue colours.

• Prism: In optics, a triangular block of transport material (plastic glass, silica) commonly used to, bend’ a ray of

light or split a beam into its special colours.

• Projectile: A particle that travels with both horizontal and vertical motion in the Earth’s gravitational field.

• Quantum mechanics: It is the part of physics that deals with radiation and the movement of atomic particles.

• Rader: An acronym for radio direction and ranging device for locating objects in space, direction finding, and

navigation by means of transmitted and reflected high-frequency radio waves.

• Radiant heat: It is energy that is radiated by all warm or hot bodies.

• Radiation: It is a kind of energy which is moving.

• Radioactivity: It is the spontaneous alteration, or decay, of the nuclei of radioactive atoms, accompanied by the

emission of radiation.

• Radiocarbon dating: It is a method of dating organic materials (for example, bone or wood), used in archaeology.

• Rainbow: It is an arch in the sky displaying the colours of the spectrum formed by the refraction and reflection of

the Sun’s rays through rain of mist.

• Reflection: The throwing back or deflection of waves, such as light or sound waves, when they hit a surface.

• Refraction: It is the bending of waves of light, heat or sound when is passes from one medium to another.

• Relativity theory: A theory that described matter, space and time and how they relate to each other.

• Retine: It is the inner layer at the back of the vertebrate eye, which contains light-sensitive cells and nerve fibres.

• Robot: It is a kind of machine that can do jobs without human help.

• Rocket: It is a projectile driven by the reaction of gases produced by a fast-burning fuel.

• Satellite: It is a kind of spacecraft.

• Satellite dish: It is a kind of aerial.

• Seismograph: It is an instruments that amplifies and record small movements of the ground caused by

earthquakes or explosions.

• Semiconductor: Crystalline material with an electrical conductivity between that of metals (good) and insulators

(poor).

• Sensor: It is a device that takes in and reacts to some kind of input energy and out puts a related electrical signal.

• Shaft: It is a rod which rotates and is connected to the axis of a wheel or a gear.

• Short circuit: It is the accidental or deliberate joining of two parts of an electric circuit by a conductor of less

resistance that allows an excessive current to flow, usually blowing a fuse.

• Silicon chip: It is a kind of crystal.

• Siphon: It is a curved pipe or tube and is used to move liquids from one container to another.

• Solder: It is an alloy and is used to join together wires and electronics components.

• Sonar: It is a device which is fitted to ship and submarines and it is used to find objects under water.

• Spectrometer: It is an instrument used to study the composition of light emitted by a source.

• Speed of light: It is the speed at which light travels through emply space. Its value is 299,792, 458 metres per

second.

• Speed of sound: It is the speed at which sound travels through a medium, such as air on water. In air at a

temperature of 00c, the speed of sound is 331 metres per second.

• Spark: A high energy discharge through a gas that lasts for a very short time, it is accompanied by a flash of light

and a sharp crackling noise.

• Solar energy: It is energy derived from the sun’s radiation.

• Solstice: One of the two times of each year when the sun reaches its maximum northerly or southerly position

among the stars. In the northern hemisphere, the summer solstice on June 21, is the longest day of the year and

winter solstice on December 21 is the shortest day of the year.

• Sound barrier: It is the point at which an aircraft attains the speed of sound.

• Superconductor: It is a substance which has no electrical resistance.

• Supersonic: It means faster that the speed of sound.

• Telescope: It is a device for collecting and focusing light and other forms of electromagnetic radiation form distant

objects.

• Thermometer: It is a device used measures temperature of hotness.

• Thermostat: It is a device used to keep the temperature in some place with in a set range.

• Tide: It is the rise and fall of sea level due to the gravitational forces of the Moon and Sun.

• Transformer: It is a device whose normal use is to transfer electrical energy with a change in voltage between

input and output.

• Transistor: It is a device for controlling the flow of minute electric current. It serves as a rectifier or as an amplifier

of current.

• Transponder: It is a transmitter cum-receiver which receive radio signals and retransmits them automatically often

at a different frequency after amplification.

• Troposphere: It is the lowest part, of the earth’s atmosphere in which most of the weather phenomena occur.

• UFO: It is an unidentified Flying Object.

• Ultrasonics: It is the study and application of the sound and vibration produced by ultrasonic pressure waves.

• Uranium: Radioactive metallic element (system U) of proton number 92 and relatives atomic mass 238.029.

• Vaporization: It is the change of state of a substance from liquid to vapour.

• Velocity: It is the speed of an object in a given direction, or the rate of change of an object’s displacement.

• VHF: It is very High frequency referring to radio waves that have very short wavelengths.

• Viscosity: Resistance of fluids (liquids and gases) to flow. It is caused by friction between the fluid molecules

moving against each other.

• Voltage: It is the electrical pressure or potential difference measured in volts.

• Voltmeter: It is an electrical instrument which measures voltage.

• Vortex: It is intense circular or whirling motion of a fluid.

• Warhead: It is the part of a missile, usually placed at the tip. containing a chemical explosive or incendiary charge

and a mechanism for setting it off. It may also carry a nuclear device.

• Water cycle: It is the continuous movement water between the ocean, atmosphere and the land. Water from the

ocean evaporates by Sun’s heat and enters the atmosphere as water vapour. The water vapour condenses and

comes down as rain from where it flows through streams and rivers into the ocean, thus completing the cycle.

• Watt: It is the unit or power, the rate of energy transfer.

• Instrument that measures atmospheric pressure as an indication of weather is Barometer

• Bicycle tyre (Pneumatic) was invented by John Boyd Dunlop

• A device used to measure current is Ammeter

• Energy from sources that are renewable and ecologically safe, as opposed to sources that are non-renewable

with toxic by-pro- ducts is Alternative energy

• Any system consisting of only two elements is Binary

• Cash Register was invented by James Ritty

• Instrument used in aircraft that measures altitude, or height above sea level is Altimeter

• Addressograph was invented by J. S. Duncan

• Metal blended with metallic some other or non-metallic substance to give it special qualities, such as resistance

to corrosion is Alloy

• Arc Lamp was invented by F. Brush

• The study of the structure of the universe and how the objects in it behave is Electronicsphysics

• Celluloid was invented by Alexander Parkes

• Adding Machine was invented by Blaise Pascal

• Carburetor was invented by Gottlieb Diamler

• The smallest unit of matter that can take part in a chemical reaction, and which cannot be broken down

chemically into anything simpler is Atom

• The science of the movement and behaviour of missiles, projectiles from guns, rifles and slings, bombs and

rockets is Ballistics

• Bifocal Lens was invented by Benjamin Franklin

• The rate of change of the velocity of a moving body is Acoustics

• The effect of the upward force (upthrust) on an object in a fluid is Orville Wright and Wilbur Wright

• In general, the experimental and theoretical science of sound and its transmission is Buoyancy

• Burglar Alarm was invented by Acoustics

• Ballpoint pen was invented by Edwin T. Holmes

• Balloon was invented by John J. Loud

• Electric Lamp was invented by Thomas Alva Edison

• The long-term pattern of weather in a region is Climate

• A negative electrode in a cell is Cathode

• Electric Motor was invented by Nikola Tesla

• Clock(Mechanical) was invented by I. Hsing and Liang Ling-Tsan

• In electronics, a term meaning ‘coded as numbers’ is Digital

• A unit of energy content of food is Calorie

• Minimum velocity with which an object must be projected for it to escape from the gravitational pull of a planetary

body is Escape velocity

• A unit of weight for gems and precious metals is Carat

• A unit of electric charge is Coulomb

• The speed of an object leaving the surface of a planet, for example, such that it just escapes the gravitational pull

is Escape speed

• The mechanical coupling of two or more spacecrafts is Docking

• A phenomenon in which a liquid rises in a thin tube or channel due to surface tension is Capillary action

• A simple generator or machine for transforming mechanical energy into electrical energy is Dynamo

• Cinema was invented by Auguste Marie Louis Nocolas Lumiere and Louis jean Lumiere

• A situation where one event causes a second this leads to a third, and so on is Chain reaction

• A beam securely fixed at one end and hanging free at the other hand is Cantilever

• An effect of surface tension is Capillarity

• Elevator was invented by Elisha G. Otis

• A unit of radioactivity is Curie

• An apparatus for measuring heat is Calorimeter

• A safety switch that automatically cuts off the current when there is an overload is Circuit breaker

• Clock (Pendulum) was invented by Christian Huygens

• The passage of an astronomical body through the shadow of another is Eclipse

• Electron is one of the basic particles of matter

• Electronic Computer was invented by J. G. Brainerd, J. P. Eckert, J. W. Mauchly

• Electric Motor was invented by Zenobe Gramme

• A force away from the centre that may appear to be observed during motion in a curve is Centrifugal force

• The atoms of an element having the same atomic number but different atomic weights are Isotopes

• A unit for measuring ship’s speed is Knot

• Sound waves which have frequencies above 500 megahertz are Hypersonic

• The branch of physics that deals with the behaviour of liquids at rest and in motion is Hydraulics

• A powerful whirling tropical storm that measures 320 to 480 kilometers in diameter is Hurricane

• Film (talking) was invented by J. Engl, J. Mussolle and H.Vogt

• Helicopter was invented by Etienne Oehmichen

• A sensitive instrument for detecting or measuring small electric currents is Galvanometer

• A point directly above the true centre of disturbance from which the shock waves of an earthquake apparently

radiate is Epicentre

• A practical unit of power which is equal to 550 foot-pound per second or 746 watts is Horse power

• The waters of the earth, oceans, lakes, rivers and glaciers that cover about three-fourth of the earth’s surface are

Hydrosphere

• A form of energy possessed by moving bodies is Kinetic energy

• Glider was invented by Sir George Cayley

• Instrument used to measure the relative density of liquids (the density compared with that of water) is Hydrometer

• Generator was invented by Piciontti