P1.5 Waves and the expanding universe Flashcards
What do waves transfer?
Energy
What are the two types of wave?
Longitudinal and transverse
In a TRANSVERSE wave what position are the oscillations in, in relation to the energy transfer?
PERPENDICULAR to the direction of energy transfer
In a LONGITUDINALwave what position are the oscillations in, in relation to the energy transfer?
PARALLEL to the direction of energy transfer
LONGITUDINAL OR TRANSVERSE?
(1) EM waves (2) Sound waves (3) Mechanical waves
(1) Transverse
(2) Longitudinal
(3) Both
What type of waves form a continuous spectrum?
EM waves
Which EM wave has: (1) The longest wavelength (2) The highest energy (3) The second to lowest frequency
(1) Radio
(2) Gamma
(3) Microwaves
What size can EM wavelengths vary from?
10^-15 metres
10^4 metres
What can longitudinal waves show?
Areas of compression and rarefaction
What is a rarefaction and what is it opposite to?
When something’s density is reduced
Opposite to compression SO IT IS LOW PRESSURE
What three things can happen to waves?
They can be Refracted, Reflected, and Diffracted
When does significant diffraction occur?
When the WAVELENGTH of the wave is of the same order of magnitude as the SIZE of the GAP/obstacle
When do waves undergo a change of direction?
When they are refracted at an interface
When are waves not refracted?
If travelling along the normal
Name four waves that can be used for communication
Radio waves
Microwaves
Infrared
Visible light
