P6 Flashcards
Absorption
when a wave transfers energy to the energy stores of a material
Alternating current
Current that is constantly changing direction
Amplitude
The maximum displacement of a point on a wave from its rest position
Angle of incidence
The angle the incident ray of a wave makes with the normal at a boundary
Angle of refraction
The angle a refracted wave makes with the normal when a wave redrafts a boundary
Atmosphere
A relatively thin layer of air that surround the earth
Control variable
keep the same
Dependent variable
variable you measure
Electromagnetic spectrum (EM)
A continuous spectrum of all the possible wavelengths of electromagnetic waves
electron
A subatomic particle with a relative charge of -1 and a relative mass of 1/2000
Energy stores
A mean by which an object stores energy. There are different types of energy stores.
Frequency
The number of waves passing a point each second, measured in hertz (Hz)
Independent variable
variable you change
Infrared (IR) radiation
A type of electromagnetic wave that is given out by all objects. It can also be absorbed by objects which makes the object hotter
Ionising radiation
Radiation that has enough energy to knock electrons off atoms
Longitudinal wave
A wave with oscillations parallel to the direction of energy transfer, e.g. sound waves
Magnetic field
Region where magnetic materials and current carrying forces experience a force
Microwaves
A type of electromagnetic wave that can be used for cooking and satellite communications
Period of a wave
Time taken for one full cycle of a wave to be completed
Radiation dose
A measure of the risk of harm to your body due to exposure of radiation
Radio wave
A type of electromagnetic wave mainly used for radio and TV signals
Radiotherapy
A treatment of cancer that uses ionising radiation as gamma rays to kill cancer cells
Ray
A straight line showing the direction of energy transfer of a wave, indicating the path along which the wave moves
Ray diagram
A diagram that shows the path of light rays
Reflection
When a wave bounces back as it meets a boundary between 2 materials
Refraction
The change in direction of a wave due to the change in velocity when moving from one medium to another
Transmission
When a wave passes through a boundary from one material into another and continues travelling
Transverse wave
A wave with oscillations perpendicular to the direction of energy transfer, e.g. electromagnetic waves
ultra violet radiation
A type of electromagnetic wave, the main source of which is sunlight
Visible light
The part of the electromagnetic spectrum that we can see with our eyes
Wave
An oscillation what transfers energy without transferring any matter
Wavelength
The length of a full cycle of a wave
X-ray
A high frequency, short wavelength. Electromagnetic wave. Used in medical treatment
Rarefaction
A region of low pressure in a longitudinal wave due to particles being spread further apart
Medium
something to go through
Vacuum
No particles
