Waves Flashcards
(20 cards)
what is wavelength?
the distance from one peak to the next
what is frequency?
how many complete waves there are per second
what is the unit for frequency?
hertz (Hz)
what is amplitude?
the height of the wave (from rest to crest)
what is the period of a wave?
the time it takes for one complete wave to pass a point
state 4 transverse waves
-light and all other EM waves
-a slinky spring wiggled up and down
-waves on strings
-ripples on water
describe transverse waves vibrations
in transverse waves the vibrations are at 90’ to the direction energy is transferred by the wave (side to side)
give 3 examples of longitudinal waves
-sound and ultrasound
-shock waves
-a silky spring when you push the end
describe a longitudinal waves vibrations
in longitudinal waves the vibrations are along he same direction as the wave transfers energy (one wave length)
what do waves transfer?
energy and information without transferring matter
give an example how a wave can transfer energy?
microwave cooking/ warming up food
give an example how waves cane be used as singles to transfer information?
light in optical fibres/ radio waves traveling through air
what do two or more waves moving together have?
wavefronts
what are wavefronts?
Imaginary planes that cut across all the waves, connecting the points on adjacent waves which are vibrating together
what is the distance between each wavefront equal to?
one wavelength
what does the doppler effect make waves go?
longer or shorter
will the waves produced by a source which is moving towards or away from an observer have the same wavelength if the source was stationary? and why?
-no it will have a different wavelength
-because the wave speed is constant so if the source is moving it ‘catches up’ to the waves in front of it
-this causes the wavefronts to bunch up in front of the moving source and spread out behind it
will the frequency of a wave be higher or lower when the source is moving away from you/ towards you
away- lower
towards- higher
will the wavelength be longer or shorter than the wave produced by the source when the source is moving away/ towards?
towards- shorter
away-longer
name all the electromagnetic waves
-radio
-micro
-infrared
-visible light
-ultra violet
-x ray
-gamma ray
