Waves (Mr Guy)

compression

an area in a wave where particles are close together

longitudinal wave

a mechanical wave in which the particles of the medium vibrate in the direction the wave is moving

matter

a substance made of particles

mechanical wave

a wave that moves energy through matter by vibrating particles

medium

a substance through which a wave can travel

rarefaction

an area in a wave where particles are spaced out

transverse wave

a wave that vibrates at right angles to its direction of motion

vacuum

empty space

wave

moving energy

amplitude

the height of a wave measured from its midpoint

frequency

the number of waves that pass a point every second

tsunami

a large sea wave caused by an earthquake

wavelength

the distance from the peak of one wave to the peak of the next wave

electromagnetic spectrum

all the different electromagnetic waves

UV

ultraviolet

pitch

the frequency of sound, measured in hertz (Hz)

sound

a mechanical wave that transfers energy through vibrating particles

volume

the loudness or amplitude of sound, measured in decibels (dB)

constant

remains the same

Doppler effect

a change in frequency as an object moves towards or away from an observer

emit

create or put out something, such as a sound

stationary

not moving

audiogram

a graph from a hearing test showing the frequency and loudness a patient can hear

cochlea

the organ of the inner ear that converts sound energy into nerve messages

infrasound

low-frequency sounds below 20 Hz

membrane

a thin layer of body tissue made of cells

pinna

the outer ear flap

ultrasound

high-frequency sounds above 20 kHz

aerophone

an instrument that produces sound by causing air to vibrate

bore

the hollow in the centre of a tube

idiophone

an instrument that produces sound through vibrating itself

membranophone

an instrument that produces sound through a vibrating, stretched membrane

neurosurgeon

a specialist doctor who operates on the brain and nervous system

receiver

a device that receives or detects sound

reflect

send back sound or light without absorbing it

therapeutic

ways of healing

transmitter

a device that produces or transmits sound

absorption

when light is not reflected by a substance but instead is turned into energy

angle of incidence

the angle at which light hits a surface

angle of reflection

the angle at which light reflects from a surface

concave

curved or rounded inwards

convex

curved or rounded outwards

normal

a line at right angles to the surface of a substance

opaque

a material that does not allow any light to pass through

reflection

when light is bounced off a surface

refraction

when light is bent as it passes from one substance to another

scattering

light rays are randomly reflected in many directions

translucent

a material that allows some light to pass through

transparent

a material that allows light to pass through

cones

light receptors in the retina that detect coloured light

eye

an organ of the body that detects light

long-sighted

a condition of the eye where light focuses behind the retina

retina

the inside, back layer of the eyeball that is made of light receptors

rods

light receptors in the retina that detect shades of light and allow us to see in black and white

short-sighted

a condition of the eye where light focuses in front of the retina

ionise

to remove an electron from an atom

neutron star

the small core left over from the collapse of a massive supergiant star when matter is compressed into a small space

star

a burning ball of gas, mostly hydrogen and helium, held together by its own gravity

supernova

the explosion caused when a star collapses and dies