Mechanical waves Flashcards
what are waves?
waves are:
energy carriers
That move energy over certain distances which results in individual particle vibrations
What are the types of waves?
Mechanical:
Requires a medium to travel through
Ex: sound, water, springs
Electromagnetic:
Require no medium
Can travel through empty space
Ex: Light, radio waves
What is a pulse? and what are the two different types of pulses?
A wave pulse is a disturbance that moves through a medium.
There is a positive wave pulse (upward curve)
and a negative wave pulse (downward curve)
What is a transverse wave?
A transverse wave is where particles in the medium vibrate perpendicular to the wave propagation
what is the amplitude of a transverse wave?
The amplitude refers to the maximum distance from the equilibrium
what is the wavelength of a transverse wave?
The horizontal distance between two adjacent crests or adjacent troughs
what is the period of a transverse wave?
The time it takes the energy to travel one wavelength
What is the frequency of a transverse wave?
The number of wavelengths that occur in one second
what are longitudinal waves?
particles in the medium that vibrate parallel to the direction the wave propagates
What is compression in a longitudinal wave?
It is the area where the medium is most dense
What is rarefaction in a longitudinal wave?
It is the area where the medium is least dense
What are the two different types of phases?
In phase:
Different waves vibrate together
Points on a wave are separated by one or multiple wavelengths
Out of phase:
Different waves do not vibrate together
Points on a wave are not separated by one or multiple wavelengths
What happens to the speed and wavelength of a wave after entering:
a slower medium?
and a faster medium?
For a slower medium, the speed and wavelength decrease
For a faster medium, the speed and wavelength increase
Does frequency change?
The frequency of a wave does not change when a wave transfers into a different medium
The frequency is solely determined by the source of the wave
What happens when a pulse meets a boundary?
When a pulse on a string meets a boundary, some or all of the wave energy will be reflected
What happens when a pulse meets a fixed boundary?
The incident pulse meets the boundary and the reflected pulse is inverted (out of phase).
What happens when a pulse meets a free boundary?
The incident pulse meets the boundary and the reflected pulse is upright in the opposite direction (in phase)
What does Transmission mean?
when a pulse moves from one spring to another it undergoes transmission
which results in the energy to be:
reflected back through the original spring
transmitted through the other spring
What happens to the reflected pulse when a pulse moves from a slow to a fast medium?
The reflected pulse is upright
What happens when to the reflected pulse when a pulse moves from a fast to a slow medium?
The reflected pulse becomes inverted
What happens in wave interference?
When two waves in opposite directions meet:
They will pass through one another
They will superimpose (amplitudes combine) and interfere
what is constructive interference?
The waves meet in phase
The sum of the two waves produce a larger waveform
What is Destructive Interference?
The waves meet out of phase
The sum cancels the waves out
What does a Wave Front Diagram show?
It shows:
The crests
The troughs
The wave propagation
