Physics P11 and P12 Flashcards
What are longitudinal waves
It’s a wave that’s parallel to the direction of energy transfer
What are transverse waves
It’s a wave that is perpendicular to the direction of energy transfer
What are examples of longitudinal waves
Sound waves
Seismic P waves
Tsunami waves
What are examples of transverse waves
All electromagnetic waves
Seismic S waves (earthquake)
What is refraction
This occurs when a wave changes a direction when crossing a boundary
Why does refraction occur
This occurs because when light is travelling through air the particles are spread out meaning the light can find gaps to go through. However, when light travels through a solid the particles are tightly arranged meaning the light has to slow down and find gaps to travel through. One side slows down which makes the light change direction.
What are electromagnetic waves
These are waves that are all transverse
Why don’t electromagnetic waves need particles to oscillate through
They don’t need particles because they oscillate through electric and magnetic fields, meaning they can travel through vacuums.
What speed does all electromagnetic waves travel at
3.8x10 8
What are the different waves
Radio Waves, Microwaves, Infrared Radiation, Visible Light, Ultra Violet, X Rays, Gamma Rays
What are carrier waves
These are waves that carry any signal.
What happens if a wave has a shorter wavelength
They will carry more information
They would have a shorter range
They would spread out less
What can Microwaves do
They can travel through the atmosphere meaning they can be used for satellite communications
What can Radiowaves do
They can reflect on the atmosphere meaning they can travel to a specific are
What are optical fibres
They are thin glass fibres that are used to transmit signals by light or infrared radiation
