4.2 What Is A Wave? Flashcards
What is a wave?
Propagation of a disturbance through a medium.
What happens as a wave travels through the medium?
Molecules of the medium are displaced from equilibrium positions, made to oscillate about these positions in simple harmonic motion.
What can a wave transfer?
Energy and momentum.
What are some examples of mechanical waves?
Water waves, sound, earthquake waves.
What medium do mechanical waves travel through?
Require a physical medium, cannot propagate in vacuum.
What is the wave speed determined by for mechanical waves?
Determined by the properties of the medium.
What is the disturbance of particles in mechanical waves?
Change of a property of the medium from its equilibrium value - when there is no waves.
What are some example of electromagnetic waves?
Light, radio waves, X rays, infrared radiation, ultraviolet radiation.
What medium do electromagnetic waves travel through?
Can propagate in a vacuum as well as various physical media.
What is the wave speed determined by for electromagnetic waves?
In vacuum all waves travel at 3x10^8 ms^-1
What is the disturbance of particles in electromagnetic waves?
The oscillating values of electric and magnetic fields.
What is displacement?
Vector to the position of a point in a medium from the equilibrium position of the point.
What is amplitude?
Maximum displacement.
What is a crest?
Maximum positive displacement.
What is a trough?
Maximum negative displacement.