What do waves transfer?
Energy, not matter.
What are the two types of waves?
Transverse and longitudinal.
What are mechanical waves?
Waves that need a medium to travel through.
What direction are transverse wave oscillations?
Perpendicular to energy transfer.
What direction are longitudinal wave oscillations?
Parallel to energy transfer.
What do longitudinal waves cause?
Compressions and rarefactions.
Example of a longitudinal wave?
Sound wave in air.
Example of a transverse wave?
Ripples on water.
What is amplitude?
Maximum displacement from rest (m).
What is frequency?
Waves per second (Hz).
What is period?
Time for one full wave (s).
What is wavelength?
Distance between two peaks/troughs (m).
What is wave speed?
Distance per second (m/s).
Equation for wave speed?
wave speed = frequency × wavelength
Equation linking period and frequency?
Time period = 1 / frequency
What are EM waves?
Transverse waves that transfer energy.
Speed of EM waves in vacuum?
3 × 10⁸ m/s
Order of EM spectrum (longest to shortest λ)?
Radio, micro, IR, visible, UV, X-rays, gamma
What is radiation dose measured in?
Sieverts (Sv)
Use of radio waves?
TV and radio signals
Use of microwaves?
Satellites, cooking food
Use of infrared?
Heaters, cameras, cooking
Use of visible light?
Fibre optic communication
Use of UV?
Sun tanning, efficient lighting
