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Physical forces and processes

absorbance

noun

the measurement of how much light an object can absorb

air resistance

noun

the way that air slows down a moving object

amplitude

noun

half of the total height of a wave such as a sound wave or an electrical wave, used as a measurement of how strong it is. The amplitude of a sea wave is its height above the level of water when the water is calm and still.

attraction

noun

a force such as gravity that pulls or keeps things together

balance

noun

the ability to remain steady in an upright position

bonding

noun

the process by which atoms join together

calorific

adjective

producing energy or heat

capillary action

noun

the force that causes a liquid to move up a narrow tube

centrifugal force

noun

an effect in which an object that is moving around a central point appears to be moved away from the centre by some force

centripetal force

noun

a force that makes things move towards the centre of something when they are moving around that centre. Gravity is the centripetal force that keeps the planets orbiting around the Sun.

chain reaction

noun

a series of chemical or physical reactions, each one of which causes the next one

condensation

noun

the process in which a gas changes into a liquid, usually when it becomes cooler

conductive

adjective

a conductive substance allows heat or electricity to pass through it

conductor

noun

a substance that allows heat or electricity to pass through it

convection

noun

the process by which the very small parts in a liquid or gas move and give out heat

decompression

noun

the process of reducing the pressure on something

deflection

noun

the amount by which something moves from its original position

diffraction

noun

the process by which sound, water, and light waves change when they pass over an object or through a narrow space

displacement

noun

the amount of water that an object pushes out of the way when it is placed in water

the Doppler effect

noun

the change that you notice in a sound, light etc as you get closer to it or further from it

drag

noun

the force that slows something down when it moves through air or liquid

E

abbreviation

energy

effect

noun

something that regularly happens, according to a law, for example in science

effort

noun

the force used on a machine of any type in order to make it able to move an object

elasticity

noun

the ability of a substance to stretch easily and then return to its original shape quickly

electromagnetic wave

noun

a wave of energy within the electromagnetic spectrum

electromagnetism

noun

magnetism that is created by electricity

energy

noun

the power that is present in all physical things and that can be changed into something such as heat, movement, or light

equilibrium

noun

a state in which an object is not moving in any way, or is moving at the same rate all the time, because there is a balance between any forces affecting it

explosion

noun

an occasion when something bursts with a lot of force and a loud noise, often causing damage

fatigue

noun

a tendency for metal or wood to break as a result of too much pressure

field

noun

an area where a particular force has an effect

flux

noun

the rate at which matter or energy flows across a surface or area

force

noun

the power or energy produced by one thing hitting another

force

noun

a power that makes an object move or that changes the way it moves

friction

noun

the physical force that makes it difficult for one surface to move over another

fusion

noun

a process in which two substances or pieces of a substance join together to form one thing

G

noun

gravity: a measurement of the force of gravity

gravitation

noun

the force that causes objects to move towards each other

gravitational

adjective

relating to the force of gravity

gravity

noun

the force that makes any two objects that have mass move towards each other. The most common example of this is when an object falls to the ground

heat

noun

the energy that is produced when the temperature of something changes

imaging

noun

the process of producing an image by using a machine that passes an electronic beam over something

impact

noun

the force with which one objects hits another

impetus

noun

a force that makes a moving object able to continue moving at the same velocity (=speed), despite any resistance (=force that slows things down)

induction

noun

the production of electrical or magnetic forces in an object by other electrical or magnetic forces near it

inertia

noun

a property of matter that makes an object stay in the same position or continue to move in a straight line until its state is changed by an external force

insulation

noun

protection from heat, cold, noise, or electricity

irradiation

noun

the visual effect by which a brightly lit thing appears larger against a dark background

jar

noun

a sudden movement when two solid things knock against each other

kinetic energy

noun

the energy that an object has as a result of moving

latent heat

noun

the heat that is taken in or given out when a substance changes its physical state, without affecting the temperature of the substance

leverage

noun

the power that a lever gives you to move things

locomotive

adjective

involving movement, or making something move

longitudinal wave

noun

a wave such as a sound wave that moves in the same direction as the movements of the particles of the substance it moves through

magnetic

adjective

a magnetic piece of metal can make iron or steel objects come to it so that they seem to stick to it

magnetic

adjective

relating to or using magnetism

magnetism

noun

the power that a magnet has to make iron or steel objects come to it so that they seem to stick to it

mechanical

adjective

relating to or produced by physical forces

moment

noun

the tendency of a force to cause a load to move. It is measured by multiplying the force by the distance from the fulcrum.

momentum

noun

the tendency of a moving object to keep moving unless another force stops it or slows it down

motive

adjective

producing or causing movement

potential energy

noun

the energy that a body or system has stored because of its position or condition. For example, a raised weight has potential energy.

pressure

noun

a force pressing on someone or something

pressure

noun

the amount of force that a gas or liquid produces in an area or container

propulsion

noun

the force that moves or pushes something forward

pull

noun

a strong physical force that causes things to move in a particular direction

reaction

noun

a physical force that is caused by an opposite physical force, usually producing a form of energy

reflection

noun

the process of reflecting light, sound, or images

relativity

noun

the relationship between time, space, and movement as described in Einstein’s ‘Theory of Relativity’

repulsion

noun

an electrical or magnetic force that makes things move away from each other

repulsive

adjective

a repulsive force makes things move away from each other

resistance

noun

a force that makes a moving object move more slowly

strength

noun

the speed or force of wind or water

stress

noun

physical pressure put on something that can make it change its shape or break

sublimation

noun

the process in which a substance is changed from a solid substance into a gas or from a gas into a solid substance without first becoming a liquid

suction

noun

the force by which two surfaces stick to each other when the air between them has been removed

superconductivity

noun

the ability of some metals to allow electricity to pass through them without any resistance at very low temperatures

surface tension

noun

the force by which the molecules of a liquid stay close together at the surface to form the smallest possible area

tensile strength

noun

the ability of something to not break when it is stretched a lot or when a lot of pressure is put on it

thrust

noun

the force that an engine produces to push something forwards

torque

noun

the force that causes something to turn around a central point

traction

noun

the action of pulling something over a surface, or the type of power used for pulling

traction

noun

the ability of wheels to move over a surface without slipping

transmission

noun

the process of sending power or energy from one place to another

transverse wave

noun

a wave such as light that makes the substance through which it moves vibrate in a direction that is at 90 degrees to the direction in which it is moving

upthrust

noun

the force that a liquid or gas directs upwards on an object that is floating on it

vector

noun

a quantity such as velocity (=speed at which something travels) that can change and is measured by its size and its direction

velocity

noun

the speed that something moves at in one direction

vibration

noun

a very small, fast, and continuous shaking movement

wave

noun

the way in which sound, light, a radio signal etc travels. It is represented by a line that curves upwards and then downwards again many times.

work

noun

the process of changing energy from one form into another, usually in order to make something move or operate

conductivity

noun

evaporation

noun

hardening

noun

magnetically

adverb

propulsive

adjective

vaporization

noun

under pressure

if a gas or liquid is under pressure, a lot of it is put into a container so that it comes out with force when the container is opened

mom jeans

a style of loose-fitting jeans with a high waist, often considered unfashionable

BuzzWord Article

Open Dictionary

endies

Employed but with No Disposable Income or Savings: people who are in work but only earn just enough to live on

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