JonyC/ScienceGlossary · Datasets at Hugging Face

term stringlengths 1 63 ⌀	category stringclasses 15 values	label int64 0 1	definition stringlengths 5 3.18k ⌀
centrifuge	Physics	1	(Noun) A machine that rotates at high speed that is used to separate materials of different densities.(Verb) To rotate at high speed.
cohesive force	Physics	1	The attractive force that holds together individual liquid molecules.
collide	Physics	1	When two or more objects, including particles, briefly come into contact with each other.
concave mirror	Physics	1	A mirror in which the reflective surface curves inwards away from the light source. Incident light is reflected inwards to one focal point. A concave mirror can be used to focus light.
conduction	Physics	1	1. Heat flow or transfer through a substance from a higher to a lower temperature. 2. Flow of electric charges through a material in response to an electric field.
conductor	Physics	1	A material or element that allows free movement of electrons and therefore allows easy flow of electricity.
constant speed	Physics	1	When the speed of an object such as a cyclist stays the same. If forces are balanced, the cyclist will travel at a constant speed.
convection current	Physics	1	Acurrent that occurs when fluid is unevenly heated so that part of the fluid rises, then cools and then sinks, producing the circular movement. This effect is caused by changes in the density of a substance when heated or cooled.
critical temperature	Physics	1	The temperature below which a material has zero electrical resistance. The critical temperature for mercury is -269 °C.
current	Physics	1	The flow of electric charge through a conductor.
dark matter	Physics	1	Is an unidentified type of matter distinct from dark energy, ordinary matter and neutrinos. The name refers to the fact that it does not emit or interact with electromagnetic radiation, such as light, and is thus invisible to the entire electromagnetic spectrum.
desorption	Physics	1	Molecules or particles are released from a surface – the reverse of adsorption.
diffraction	Physics	1	The bending of waves as they pass small obstacles and the spreading out of waves after passing through small openings.
diffuse reflection	Physics	1	The reflection of light from a rough surface in which the incident light rays are reflected from the surface at many different angles.
diffusion	Physics	1	The movement of atoms or molecules from an area of higher concentration to an area of lower concentration. Atoms and small molecules can move across a cell membrane by diffusion.
dynamic	Physics	1	In science, a process or system characterised by constant change.
effusion	Physics	1	A process that involves gas molecules escaping through a small hole in a containing vessel. It explains why inflated toy balloons deflate when left alone for several days.
electrode	Physics	1	Terminal where electricity goes in or out of a conductor, for example, the positive and negative terminals of a battery.
electromagnetic spectrum	Physics	1	The complete range of electromagnetic radiation from the shortest waves (gamma rays) to the longest (radio waves).
electrophoresis	Physics	1	When an electrical current is applied to a solution to separate out different sized particles, the most common use being DNA gel electrophoresis.
electrostatic	Physics	1	Electric charge that is stationary.
electrostatic forces	Physics	1	The forces that occur between electrically charged objects.
energy dispersive x-ray analysis	Physics	1	Also known as EDXA, this is a technique used to determine the individual elements of an object. An electron beam is passed over the sample, which causes X-rays to be emitted from the sample. The energy of the X-rays emitted varies with different elements, which enables scientists to obtain an image of each element in the sample. As X-rays are of low intensity, this process can take several hours.
evaporative cooling	Physics	1	A reduction in temperature due to the evaporation of a liquid, such as water, from a surface. The temperature reduction depends upon the magnitude of the latent heat of vaporisation of the liquid concerned.
fahrenheit	Physics	1	A temperature scale named after 18thcentury German physicist Daniel Gabriel Fahrenheit. The freezing point of water is defined as 32 °F and the boiling point of water as 212 °F.
flammable	Physics	1	Easily ignited or set on fire.
fluoresce	Physics	1	Produce light when exposed to radiation of a particular wavelength.
fluorescence	Physics	1	The giving out of light when atoms are excited by an external energy source, such as light (but not heat).
focus	Physics	1	The point on a fault where the first break happens, and where the seismic waves radiate out from.
gases	Physics	1	The state of matter distinguished from the solid and liquid states. Gases have the ability to diffuse readily and to become distributed uniformly throughout any container.
gluon	Physics	1	An elementary particle that carries the strong, or nuclear, force. Quarks that make up protons and neutrons are effectively ‘glued’ together by gluons.
gravitational microlensing	Physics	1	Einstein predicted that a star warps the space surrounding it, enabling the star to act like a giant magnifying glass. Astronomers use this bending of light rays by the gravitational field of a massive object (the lens) to magnify the light of background objects such as distant stars that are within the line of sight of the lens. This means that astronomers can now study massive objects no matter how faint as long as they are able to use another brighter closer object to magnify the dim object. They now use this technique to study faint or dark objects such as brown dwarfs, red dwarfs, planets, white dwarfs, neutron stars and black holes.
gravitational potential energy	Physics	1	The energy gained by an object as its height above ground level increases.
gravity load	Physics	1	Vertical forces that act on a structure.
heat energy	Physics	1	Heat energy: the transfer of energy in materials from the random movement of the particles in that material. The greater the random movement of particles the more heat energy the material has. Temperature is a measure of the heat energy of a material.Heat: the flow of energy from a warm object to a cooler object.
helmholtz resonator	Physics	1	A structure where pressure fluctuations over the opening causes the fluid or air inside to resonate, forming an audible sound, for example, the sound generated by blowing across the top of a bottle.
hypersonic	Physics	1	Anything travelling faster than five times the speed of sound (faster than about 1650 m/s or 6000 km/h in air).
induced drag	Physics	1	Resistance that is a consequence of lift. It is caused by airflow passing over a wing.
interference	Physics	1	The simultaneous presence of two or more waves in the same position, resulting in a new wave pattern.
ion exchange	Physics	1	A reversible process where ions are swapped between different substances on the basis of their electrical charge.
ionise	Physics	1	The process involving either the addition or removal of electrons from an atom or molecule to form an ion. An ion carries a positive or negative charge.
joint european torus	Physics	1	The Joint European Torus (JET) is a nuclear fusion plasma physics experimental facility located in Oxfordshire in the UK. The core structure of the facility is a tokamak reactor, within which fusion reactions are made to occur.
jet	Physics	1	The Joint European Torus (JET) is a nuclear fusion plasma physics experimental facility located in Oxfordshire in the UK. The core structure of the facility is a tokamak reactor, within which fusion reactions are made to occur.
kinetic	Physics	1	Relating to motion or movement.
kinetic-molecular theory of matter	Physics	1	The theory has been developed to explain experimental observations of the behaviour of solids, liquids and gases. The two major assumptions that underpin the theory are that all matter is composed of tiny particles and that these particles are in constant motion.
latent heat	Physics	1	The heat necessary to transform from one state of matter (i.e. solid) to another (i.e. liquid) without a rise in temperature until the change is completed.
light energy	Physics	1	Electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye.
light spectrum	Physics	1	Electromagnetic waves in the range visible to the human eye. These waves have a wavelength from about 400 nanometres in the violet to about 770 nanometres in the red. Light behaves both as a particle and a wave. A particle of light is known as a photon.
visible	Physics	1	Electromagnetic waves in the range visible to the human eye. These waves have a wavelength from about 400 nanometres in the violet to about 770 nanometres in the red. Light behaves both as a particle and a wave. A particle of light is known as a photon.
light year	Physics	1	A unit of distance. Approximately 9.5 trillion kilometres (9,500,000,000,000 km), which is how far light travels in a year.
magnet	Physics	1	An object that generates a magnetic field that can influence magnetic objects such as iron and other metals.
mass	Physics	1	The amount of matter an object has, measured in kilograms.
mass spectrometer	Physics	1	An instrument that can measure the mass of atoms.
meissner effect	Physics	1	When a superconductor is cooled below its critical temperature, it has the ability to expel an applied magnetic field. This effect can be demonstrated by levitating a small magnet above a suitably cooled superconductor.
melting point	Physics	1	The temperature at which a substance changes state from a solid to a liquid.
microwaves	Physics	1	Invisible electromagnetic waves with wavelengths ranging from 1 mm to 1 m. Microwaves occur between radio and infrared waves on the electromagnetic spectrum.
moment of a force	Physics	1	An alternative name for torque.
monochromatic light	Physics	1	Light of one colour. All wavelengths are the same or confined to a very narrow range. For example, red light visible to the human eye covers the wavelength range from 630–740 nm.
nanoparticle	Physics	1	A particle that has at least one dimension of 100 nm or less. Nanoparticles tend to have different properties to the same material at a larger size.
neon	Physics	1	Neon is a noble gas with the symbol Ne and atomic number 10. It is the second-lightest noble gas, after helium.
newton	Physics	1	The unit of measurement of a force (N), named after the famous English physicist Sir Isaac Newtonwhose laws of motion and gravity underpin much of modern day physics.
newtonian fluid	Physics	1	A fluid that maintains constant flow rate regardless of the amount of stress applied.
nobel prize	Physics	1	An annual, prestigious international award for achievement in physics, chemistry, physiology or medicine, literature and peace.
noble gas	Physics	1	Gases in Group 18 of the periodic table, often called inert gases. They are not very reactive due to the stability of their electron structure.
non-newtonian fluid	Physics	1	A fluid that changes in flow rate depending on the amount of stress or length of time that stress is applied.
nuclear fission	Physics	1	A nuclear reaction in which an atomic nucleus, especially a heavy nucleus such as an isotope of uranium, splits into fragments. Usually, two fragments of comparable mass are produced along with several neutrons. A large amount of energy is released during the process.
nuclear fusion	Physics	1	The process by which multiple atomic particles join together to form a heavier nucleus. This process is accompanied by the release or absorption of energy. The Sun produces heat and light by the nuclear fusion of hydrogen atoms into helium atoms.
nuclear radiation	Physics	1	High energy particles or rays emitted during the nuclear decay processes.
nuclear reaction	Physics	1	A reaction that involves a change in the composition of a nucleus and can evolve or absorb an extraordinarily large amount of energy.
nuclear reactor	Physics	1	A system in which controlled nuclear fission reactions generate heat energy on a large scale, which is subsequently converted into electrical energy.
opaque	Physics	1	A substance that does not allow light to pass through it.
p-waves	Physics	1	Seismic waves that travel as compressions (similar to how sound travels). They can travel through solid and liquid.
paleomagnetic dating	Physics	1	A type of dating method that examines the way magnetic iron particles are oriented in a sample and compares this with known movements of the magnetic North Pole over geologic time.
paramagnetic	Physics	1	Very weakly attracted by the poles of a magnet but not retaining any permanent magnetism.
paramagnetism	Physics	1	A form of magnetism that occurs only in the presence of an externally applied magnetic field. Paramagnetic materials are attracted to magnetic fields, but they do not retain any magnetisation in the absence of an externally applied magnetic field.
parameters	Physics	1	Limits of measurement.
particle	Physics	1	A tiny piece of matter. A particle may refer to an atom, part of an atom, a molecule or an ion.
particle accelerator	Physics	1	A device, such as a cyclotron or linear accelerator, that accelerates charged subatomic particles or nuclei to high energies. Also called an atom smasher.
pascal	Physics	1	(Pa) Derived SI unit of pressure – 1 pascal = 1 newton per square metre.
petrophysics	Physics	1	The study of physical and chemical rock properties and their interactions with fluids.
phosphor	Physics	1	A substance that emits light when excited by electromagnetic radiation.
phostrex	Physics	1	A fire suppression agent developed for aviation applications.
photoelectric effect	Physics	1	Given the right conditions, when light with sufficient energy is shone onto a metal surface, electrons can be emitted or ejected from the surface of the metal. The energies of the emitted electrons are independent of the intensity of the incident light.
phreatomagmatic	Physics	1	A type of volcanic explosion where the emerging magma meets water (either groundwater or seawater), causing a violent eruption. The water becomes superheated while the magma is rapidly chilled.
physical sciences	Physics	1	The sciences that explore the study of inanimate natural objects, including physics, chemistry, astronomy and related subjects.
physiological	Physics	1	The function of organs and organ systems and how they work within a living organism to respond to external and internal challenges.
plasma	Physics	1	1. The fourth state of matter – a gas that is ionised and consists of positive and negative ions (or particles), with no overall charge. It is affected by magnetic fields and has high electrical conductivity. 2. The colourless or pale yellow liquid in blood and lymph.
polarised light	Physics	1	Light made up of waves that all oscillate in the same direction.
positron	Physics	1	A particle with the same mass and size of charge as an electron, but it has a positive charge – a positive electron.
pressure drag	Physics	1	A type of drag caused by the difference in air pressure between the front and back surfaces of an object as it moves through the air (or other fluid).
proton	Physics	1	Elementary particle with a single positive electrical charge.
psi	Physics	1	Pounds per square inch (psi) is a non-SI unit of pressure – 1 psi = 6.895 kilopascals.
pulsed field gel electrophoresis	Physics	1	A technique designed to separate large fragments of DNA by ‘pulsing’ a current of electricity in alternate directions to DNA in a gel matrix.
quantum dot	Physics	1	A semiconductor nanocrystal, which can give out light when excited. Different size particles give off different colours.
radial velocity	Physics	1	The speed of something as it moves directly towards, or away from, an observer.
radiant energy	Physics	1	Energy transferred by radiation, especially by an electromagnetic wave.
radiate	Physics	1	To emit, extend or spread rays from a central point.
radiation	Physics	1	Energy that is transmitted (radiates) from a source in the form of rays or waves or particles.
radioactive	Physics	1	Giving off energy as a result of the breaking up of nuclei of atoms. Something undergoing radioactive decay, the process by which an unstable atom emits radiation.
radioactive decay	Physics	1	The process in which an unstable atomic nucleus loses energy by emitting radiation. This decay, or loss of energy, results in an atom of one type, called the parent nuclide, transforming to an atom of a different type, called the daughter nuclide. The average time interval required for one-half of any quantity of identical radioactive atoms to undergo radioactive decay is called half life.

centrifuge

Physics

1

(Noun) A machine that rotates at high speed that is used to separate materials of different densities.(Verb) To rotate at high speed.

cohesive force

Physics

1

The attractive force that holds together individual liquid molecules.

collide

Physics

1

When two or more objects, including particles, briefly come into contact with each other.

concave mirror

Physics

1

A mirror in which the reflective surface curves inwards away from the light source. Incident light is reflected inwards to one focal point. A concave mirror can be used to focus light.

conduction

Physics

1

1. Heat flow or transfer through a substance from a higher to a lower temperature. 2. Flow of electric charges through a material in response to an electric field.

conductor

Physics

1

A material or element that allows free movement of electrons and therefore allows easy flow of electricity.

constant speed

Physics

1

When the speed of an object such as a cyclist stays the same. If forces are balanced, the cyclist will travel at a constant speed.

convection current

Physics

1

Acurrent that occurs when fluid is unevenly heated so that part of the fluid rises, then cools and then sinks, producing the circular movement. This effect is caused by changes in the density of a substance when heated or cooled.

critical temperature

Physics

1

The temperature below which a material has zero electrical resistance. The critical temperature for mercury is -269 °C.

current

Physics

1

The flow of electric charge through a conductor.

dark matter

Physics

1

Is an unidentified type of matter distinct from dark energy, ordinary matter and neutrinos. The name refers to the fact that it does not emit or interact with electromagnetic radiation, such as light, and is thus invisible to the entire electromagnetic spectrum.

desorption

Physics

1

Molecules or particles are released from a surface – the reverse of adsorption.

diffraction

Physics

1

The bending of waves as they pass small obstacles and the spreading out of waves after passing through small openings.

diffuse reflection

Physics

1

The reflection of light from a rough surface in which the incident light rays are reflected from the surface at many different angles.

diffusion

Physics

1

The movement of atoms or molecules from an area of higher concentration to an area of lower concentration. Atoms and small molecules can move across a cell membrane by diffusion.

dynamic

Physics

1

In science, a process or system characterised by constant change.

effusion

Physics

1

A process that involves gas molecules escaping through a small hole in a containing vessel. It explains why inflated toy balloons deflate when left alone for several days.

electrode

Physics

1

Terminal where electricity goes in or out of a conductor, for example, the positive and negative terminals of a battery.

electromagnetic spectrum

Physics

1

The complete range of electromagnetic radiation from the shortest waves (gamma rays) to the longest (radio waves).

electrophoresis

Physics

1

When an electrical current is applied to a solution to separate out different sized particles, the most common use being DNA gel electrophoresis.

electrostatic

Physics

1

Electric charge that is stationary.

electrostatic forces

Physics

1

The forces that occur between electrically charged objects.

energy dispersive x-ray analysis

Physics

1

Also known as EDXA, this is a technique used to determine the individual elements of an object. An electron beam is passed over the sample, which causes X-rays to be emitted from the sample. The energy of the X-rays emitted varies with different elements, which enables scientists to obtain an image of each element in the sample. As X-rays are of low intensity, this process can take several hours.

evaporative cooling

Physics

1

A reduction in temperature due to the evaporation of a liquid, such as water, from a surface. The temperature reduction depends upon the magnitude of the latent heat of vaporisation of the liquid concerned.

fahrenheit

Physics

1

A temperature scale named after 18thcentury German physicist Daniel Gabriel Fahrenheit. The freezing point of water is defined as 32 °F and the boiling point of water as 212 °F.

flammable

Physics

1

Easily ignited or set on fire.

fluoresce

Physics

1

Produce light when exposed to radiation of a particular wavelength.

fluorescence

Physics

1

The giving out of light when atoms are excited by an external energy source, such as light (but not heat).

focus

Physics

1

The point on a fault where the first break happens, and where the seismic waves radiate out from.

gases

Physics

1

The state of matter distinguished from the solid and liquid states. Gases have the ability to diffuse readily and to become distributed uniformly throughout any container.

gluon

Physics

1

An elementary particle that carries the strong, or nuclear, force. Quarks that make up protons and neutrons are effectively ‘glued’ together by gluons.

gravitational microlensing

Physics

1

Einstein predicted that a star warps the space surrounding it, enabling the star to act like a giant magnifying glass. Astronomers use this bending of light rays by the gravitational field of a massive object (the lens) to magnify the light of background objects such as distant stars that are within the line of sight of the lens. This means that astronomers can now study massive objects no matter how faint as long as they are able to use another brighter closer object to magnify the dim object. They now use this technique to study faint or dark objects such as brown dwarfs, red dwarfs, planets, white dwarfs, neutron stars and black holes.

gravitational potential energy

Physics

1

The energy gained by an object as its height above ground level increases.

gravity load

Physics

1

Vertical forces that act on a structure.

heat energy

Physics

1

Heat energy: the transfer of energy in materials from the random movement of the particles in that material. The greater the random movement of particles the more heat energy the material has. Temperature is a measure of the heat energy of a material.Heat: the flow of energy from a warm object to a cooler object.

helmholtz resonator

Physics

1

A structure where pressure fluctuations over the opening causes the fluid or air inside to resonate, forming an audible sound, for example, the sound generated by blowing across the top of a bottle.

hypersonic

Physics

1

Anything travelling faster than five times the speed of sound (faster than about 1650 m/s or 6000 km/h in air).

induced drag

Physics

1

Resistance that is a consequence of lift. It is caused by airflow passing over a wing.

interference

Physics

1

The simultaneous presence of two or more waves in the same position, resulting in a new wave pattern.

ion exchange

Physics

1

A reversible process where ions are swapped between different substances on the basis of their electrical charge.

ionise

Physics

1

The process involving either the addition or removal of electrons from an atom or molecule to form an ion. An ion carries a positive or negative charge.

joint european torus

Physics

1

The Joint European Torus (JET) is a nuclear fusion plasma physics experimental facility located in Oxfordshire in the UK. The core structure of the facility is a tokamak reactor, within which fusion reactions are made to occur.

jet

Physics

1

The Joint European Torus (JET) is a nuclear fusion plasma physics experimental facility located in Oxfordshire in the UK. The core structure of the facility is a tokamak reactor, within which fusion reactions are made to occur.

kinetic

Physics

1

Relating to motion or movement.

kinetic-molecular theory of matter

Physics

1

The theory has been developed to explain experimental observations of the behaviour of solids, liquids and gases. The two major assumptions that underpin the theory are that all matter is composed of tiny particles and that these particles are in constant motion.

latent heat

Physics

1

The heat necessary to transform from one state of matter (i.e. solid) to another (i.e. liquid) without a rise in temperature until the change is completed.

light energy

Physics

1

Electromagnetic radiation, particularly radiation of a wavelength that is visible to the human eye.

light spectrum

Physics

1

Electromagnetic waves in the range visible to the human eye. These waves have a wavelength from about 400 nanometres in the violet to about 770 nanometres in the red. Light behaves both as a particle and a wave. A particle of light is known as a photon.

visible

Physics

1

Electromagnetic waves in the range visible to the human eye. These waves have a wavelength from about 400 nanometres in the violet to about 770 nanometres in the red. Light behaves both as a particle and a wave. A particle of light is known as a photon.

light year

Physics

1

A unit of distance. Approximately 9.5 trillion kilometres (9,500,000,000,000 km), which is how far light travels in a year.

magnet

Physics

1

An object that generates a magnetic field that can influence magnetic objects such as iron and other metals.

mass

Physics

1

The amount of matter an object has, measured in kilograms.

mass spectrometer

Physics

1

An instrument that can measure the mass of atoms.

meissner effect

Physics

1

When a superconductor is cooled below its critical temperature, it has the ability to expel an applied magnetic field. This effect can be demonstrated by levitating a small magnet above a suitably cooled superconductor.

melting point

Physics

1

The temperature at which a substance changes state from a solid to a liquid.

microwaves

Physics

1

Invisible electromagnetic waves with wavelengths ranging from 1 mm to 1 m. Microwaves occur between radio and infrared waves on the electromagnetic spectrum.

moment of a force

Physics

1

An alternative name for torque.

monochromatic light

Physics

1

Light of one colour. All wavelengths are the same or confined to a very narrow range. For example, red light visible to the human eye covers the wavelength range from 630–740 nm.

nanoparticle

Physics

1

A particle that has at least one dimension of 100 nm or less. Nanoparticles tend to have different properties to the same material at a larger size.

neon

Physics

1

Neon is a noble gas with the symbol Ne and atomic number 10. It is the second-lightest noble gas, after helium.

newton

Physics

1

The unit of measurement of a force (N), named after the famous English physicist Sir Isaac Newtonwhose laws of motion and gravity underpin much of modern day physics.

newtonian fluid

Physics

1

A fluid that maintains constant flow rate regardless of the amount of stress applied.

nobel prize

Physics

1

An annual, prestigious international award for achievement in physics, chemistry, physiology or medicine, literature and peace.

noble gas

Physics

1

Gases in Group 18 of the periodic table, often called inert gases. They are not very reactive due to the stability of their electron structure.

non-newtonian fluid

Physics

1

A fluid that changes in flow rate depending on the amount of stress or length of time that stress is applied.

nuclear fission

Physics

1

A nuclear reaction in which an atomic nucleus, especially a heavy nucleus such as an isotope of uranium, splits into fragments. Usually, two fragments of comparable mass are produced along with several neutrons. A large amount of energy is released during the process.

nuclear fusion

Physics

1

The process by which multiple atomic particles join together to form a heavier nucleus. This process is accompanied by the release or absorption of energy. The Sun produces heat and light by the nuclear fusion of hydrogen atoms into helium atoms.

nuclear radiation

Physics

1

High energy particles or rays emitted during the nuclear decay processes.

nuclear reaction

Physics

1

A reaction that involves a change in the composition of a nucleus and can evolve or absorb an extraordinarily large amount of energy.

nuclear reactor

Physics

1

A system in which controlled nuclear fission reactions generate heat energy on a large scale, which is subsequently converted into electrical energy.

opaque

Physics

1

A substance that does not allow light to pass through it.

p-waves

Physics

1

Seismic waves that travel as compressions (similar to how sound travels). They can travel through solid and liquid.

paleomagnetic dating

Physics

1

A type of dating method that examines the way magnetic iron particles are oriented in a sample and compares this with known movements of the magnetic North Pole over geologic time.

paramagnetic

Physics

1

Very weakly attracted by the poles of a magnet but not retaining any permanent magnetism.

paramagnetism

Physics

1

A form of magnetism that occurs only in the presence of an externally applied magnetic field. Paramagnetic materials are attracted to magnetic fields, but they do not retain any magnetisation in the absence of an externally applied magnetic field.

parameters

Physics

1

Limits of measurement.

particle

Physics

1

A tiny piece of matter. A particle may refer to an atom, part of an atom, a molecule or an ion.

particle accelerator

Physics

1

A device, such as a cyclotron or linear accelerator, that accelerates charged subatomic particles or nuclei to high energies. Also called an atom smasher.

pascal

Physics

1

(Pa) Derived SI unit of pressure – 1 pascal = 1 newton per square metre.

petrophysics

Physics

1

The study of physical and chemical rock properties and their interactions with fluids.

phosphor

Physics

1

A substance that emits light when excited by electromagnetic radiation.

phostrex

Physics

1

A fire suppression agent developed for aviation applications.

photoelectric effect

Physics

1

Given the right conditions, when light with sufficient energy is shone onto a metal surface, electrons can be emitted or ejected from the surface of the metal. The energies of the emitted electrons are independent of the intensity of the incident light.

phreatomagmatic

Physics

1

A type of volcanic explosion where the emerging magma meets water (either groundwater or seawater), causing a violent eruption. The water becomes superheated while the magma is rapidly chilled.

physical sciences

Physics

1

The sciences that explore the study of inanimate natural objects, including physics, chemistry, astronomy and related subjects.

physiological

Physics

1

The function of organs and organ systems and how they work within a living organism to respond to external and internal challenges.

plasma

Physics

1

1. The fourth state of matter – a gas that is ionised and consists of positive and negative ions (or particles), with no overall charge. It is affected by magnetic fields and has high electrical conductivity. 2. The colourless or pale yellow liquid in blood and lymph.

polarised light

Physics

1

Light made up of waves that all oscillate in the same direction.

positron

Physics

1

A particle with the same mass and size of charge as an electron, but it has a positive charge – a positive electron.

pressure drag

Physics

1

A type of drag caused by the difference in air pressure between the front and back surfaces of an object as it moves through the air (or other fluid).

proton

Physics

1

Elementary particle with a single positive electrical charge.

psi

Physics

1

Pounds per square inch (psi) is a non-SI unit of pressure – 1 psi = 6.895 kilopascals.

pulsed field gel electrophoresis

Physics

1

A technique designed to separate large fragments of DNA by ‘pulsing’ a current of electricity in alternate directions to DNA in a gel matrix.

quantum dot

Physics

1

A semiconductor nanocrystal, which can give out light when excited. Different size particles give off different colours.

radial velocity

Physics

1

The speed of something as it moves directly towards, or away from, an observer.

radiant energy

Physics

1

Energy transferred by radiation, especially by an electromagnetic wave.

radiate

Physics

1

To emit, extend or spread rays from a central point.

radiation

Physics

1

Energy that is transmitted (radiates) from a source in the form of rays or waves or particles.

radioactive

Physics

1

Giving off energy as a result of the breaking up of nuclei of atoms. Something undergoing radioactive decay, the process by which an unstable atom emits radiation.

radioactive decay

Physics

1

The process in which an unstable atomic nucleus loses energy by emitting radiation. This decay, or loss of energy, results in an atom of one type, called the parent nuclide, transforming to an atom of a different type, called the daughter nuclide. The average time interval required for one-half of any quantity of identical radioactive atoms to undergo radioactive decay is called half life.