p5-waves basic waves, superposition, interference Flashcards
What is the Amplitude of a wave ?
A waves maximum displacement from the equilibrium position
What is the wavelength of a wave?
The distance between two identical points on a wave/ the length of one whole oscillation
what is the period of a wave?
The time it takes for the wave to repeat itself at a given point/ Time taken for one oscillation
What is the frequency of a wave?
The number of complete oscillations passing through a point per second
How are period and frequency linked ?
frequency=1/ period and period=1/frequency
What is superposition?
When two or more waves cross at a point, the displacement at that point is equal to the sum of the displacement of individual waves.
What is the definition of phase?
The position of a certain point om a wave cycle. This can be measured in radians or degrees or a fraction of a cycle
What is phase difference?
How much a particle/ wave lags behind another particle/wave. This can be measured in radians, degrees or fractions of a cycle
What is path difference?
The difference in distance travelled by two waves
What is coherence?
when the waves have the same frequency and a constant phase difference
What is a wavefront?
A wavefront is a surface which is used to represent the points of a wave which have the same phase.
What is the phase relationship between phase difference and path difference?
They are directly proportional?
What is the equation for phase difference?
phase difference= 360x path difference/wavelength
What is the minima of a wave?
The point where a crest and a trough of two different wavefronts meet
What is the maxima of a wave?
The point where two crests or two troughs of two different waves meet
what is the equation for working out the velocity of a wave?
wave speed=frequency x wavelength
What are longitudinal waves?
The oscillations parallel to the direction of energy transfer.
These are made up of compressions and rarefactions.
Cannot travel in a vacuum.
What is happening at rarefactions?
Low pressure.
Neighbouring particles move away from one another.
What is happening at compressions?
High pressure.
Neighbouring particles move towards a particle.
What are transverse waves?
The oscillations are perpendicular to the direction of the wave.
Consist of peaks and troughs.
Can travel in a vacuum.
What is an S-wave ?
They are transverse waves that travel through the earth in a earthquake, they can travel through liquid so arrive after P-waves as they are slower.
What are P-waves?
They are longitudinal waves that travel thought the earth in a earthquake. They cannot travel through liquid and are faster so arrive at the surface first.
What can a Displacement/ Distance graph show for a wave?
Shows the displacement of a particle with the distance the wave travels. Used to measure the wave length.
What can Displacement/Time graph show for a wave?
Show the displacement of a particle varies with time. Can be used to measure the period of a wave.