Waves Flashcards
What does a progressive wave do
Transfers energy without transferring matter
What is the amplitude of a wave
Maximum magnitude of displacement; from rest to crest
What is frequency of a wave
No of vibrations per second
What is phase difference
The distance one wave travels in front of/behind another
What are transverse waves with 2 examples
Waves which vibrate perpendicular to energy transfer, eg light or waves on a string
What are longitudinal waves with 2 examples
Waves which vibrate parallel/along direction of energy transfer, eg sound waves and springs
What does it mean if a wave is polarised
Its vibration are restricted to one direction
When does superposition occur
When 2 waves pass through each other
What is constructive interference
When 2 waves are in phase, eg a crest + a crest gives a bigger crest
What is destructive interference
When 2 waves are half a cycle out of phase, eg a crest + a trough of equal size destruct totally
When are 2 sources coherent
When they have the same wavelength and frequency, and a fixed phase difference between them
What is a stationary wave
The superposition of 2 progressive waves with the same frequency, moving in the opposite direction
