waves Flashcards
what do waves transfer
energy
what do mechanical waves travel through
a medium (matter)
whatre all waves categorised into
transverse or longitudinal
describe an give an example for transferse waves
they osciate perpendiculat to the direction of energy transfer. electromagnetic waves
describe and give an example of longitudinal waves
they osscilate parallel to the direction of energy transfer, sound and water waves
whats the equation to calculate wave speed
wavespeed=frequency x wavelength
whatre compressions and rarefactions
in longitudinal waves
-compression is when the waves are close together
-rarefaction is when theyre spread lut
what happens to waves at a boundary between 2 different matierials
theyre either
-reflected
-transmitted
-absorbed
whats refraction
when waves change direction as they cross from 1 medium to another due to a change in velocity
incident ray and incident angle =..
reflected ray and reflected angle
whatre the 5 different ways to descrube wave motion
-frequency in Hz
-wavelentj
-period (1/f)
-amplitude
-wavefront
whatre electromegnetic waves
transferve waves that tranfer energy from the source of thw wave to an absorber
whats the wavespeed of all transferve waves
300 million m/s
name all the waves in the electromegnetic spectrum
RAW MEAT IS VERY UNSANITARY EXCEPT GIRRAFES
-radio waves
-microwaves
-visible light
-ultraviolet
-xrays
-gamma rays
what happens as you go across the spectrum
-wavelength decreases ans frequency increases
whats meant by diffraction
the spreading out of waves as they apass through a gap or obsticle
what happens to diffraction when the gap is narrow
the waves spread further away from the gap
how do we see different visible light
its detected by our eyes in terms of wavelength
all objects —- and —– infrared radiation
emmit and absorb
what does the frequency and amount of emitted radiation depend on
the temp and surface of a given object
-hotter -> more radiaton emitted
what 4 waves are used for communication
-microwaves
-radiowaves
-infrared
-visible light
whats an optical fiber
thin and transparent fibers that transfer signals by either visible light or infrared radiation
why are shorter radiowaves more useful in communications
because they can carry more info without a weakend signal and theyre more easily absorbed
whatre the uses of radiowaves
-tv systems
-radio systems
-bluetooth
whatre the uses of microwaevs
- mobile phones
-satalites
-microwave ovens (when waves are absorbed by water molecules)
whatre the uses of infrared rays
- tv remote controls
-night vision devices
-heating
whatre the uses of visible light
-optic fiber communications, photography