Waves Flashcards
What are two examples of longitudinal waves?
> sound
> longitudinal seismic waves
What does a mechanical wave mean?
> one that needs a medium to travel through
What does an electromagnetic wave mean?
> one that does not require a medium to travel through
In a longitudinal wave, what is the squashed part called?
> a compression
In a longitudinal wave, what is the stretched out part called?
> a rarefaction
The oscillation of a transverse wave is…
Perpendicular to the direction of the wave
How is a transverse wave created?
> by an up and down movement (oscillation)
For a longitudinal wave, the oscillation is…
parallel to the direction of the wave
What are two examples of transverse waves?
> light
> radio
What does the amount of diffraction depend on?
> the length of the wavelength in relation to the size of the gap
> longer the wavelength or smaller the gap, the more the wave spreads out.
How can diffraction be described?
> waves spreading out
What is refraction?
> when a wave changes direction as it enters a different medium
What happens if a wave hits the boundary of a different medium face on?
> it will continue moving in the same direction
What happens if a wave hits a different medium at an angle?
> it will be refracted
What is needed for maximum diffraction to occur?
> the gap needs to be the same size as the wavelength
What are the qualities of an image reflected by a plane mirror?
> virtual
> upright
> laterally inverted
What do all electromagnetic waves have in common?
> all transfer energy
> can all travel through a vacuum
> all travel at the speed of light through a vacuum
What is the order for electromagnetic waves?
> gamma
> x-Ray
> ultraviolet
> visible light
> infrared
> microwaves
> radio waves
What are the four electromagnetic waves used in communication?
> radio
> microwave
> infrared
> light
What two types of waves do mobile phones use?
> microwaves
> radio waves
What methods of communication use radio waves?
> radio
> TV
> Bluetooth for headsets
> mobile phones
What methods of communication use micro waves?
> mobile phones
> TV signal
What methods of communication use infrared waves?
> TV remote controls
> fibre optic cables for Internet
What two electromagnet waves are used by fibre optic cables? Why?
> visible light
> infrared radiation
> because there is almost no loss of signal
What is sound caused by?
Vibrations
What is loudness if a sound wave determined by?
> amplitude
What is pitch of a sound wave determined by?
> frequency
What is an echo?
> a reflection of sound
