4.4.1 Wave Motion Flashcards
Progressive Waves, Graphs of Waves, Describing Waves
What is a progressive wave?
An oscillation that travels through matter, transferring energy from one place to another.The particles in the matter vibrate but do not move along the wave.
Why is sound a progressive wave?
When hearing sound, vibrations travel to your ears, but the air particles do not. instead they vibrate in a plane parallel to the direction of energy transfer as the wave passes through the air.
What are transverse waves?
The oscillations or vibrations in a transverse wave are perpendicular to the direction of energy transfer.
Give an example of a transverse wave.
-Waves on the surface of water
-Any electromagnetic wave
What is a longitudinal wave?
In a longitudinal wave, the oscillations are parallel to the direction of energy transfer.They create a series of rarefactions and compressions.
Give examples of longitudinal waves.
-sound waves
- P waves produced in earthquakes
Define a region of rarefaction.
Regions of low pressure due to particles being spread further apart.
Define a region of compression
Regions of high pressure due to particles being close together.
Define the time period for an oscillation.
The time taken for a wave to move one whole wavelength past a given point/ the time taken for one oscillation.
Define the frequency of an oscillation.
The number of wavelengths passing a given point per unit time.
How are time period and frequency related?
Frequency is inversely proportional to the time period; f= 1/T
State the wave equation.
speed= frequency x wavelength
What is a wave profile?
A graph showing the displacement of the particles in the wave against the distance along the wave.
What is phase difference?
The difference between the displacements of particles along a wave.
What are the units of phase difference?
360 degrees = 2pie radians
