7. Wave Characteristics & Periodic Motion Flashcards
what is a wave the transfer of
energy and momentum from one point to another
what are the 2 types of mechanical waves
transverse and longitudinal
what are transverse waves in terms of what they do to the medium
medium displaced perpendicularly to direction the wave is travelling
what are longitudinal waves in terms of what they do to the medium
causes medium to be displaced parallel to the direction the wave is travelling
what is the wavelength
measured from one point in the wave to the point where the wave repeats itself
what unit is wavelengths measured in
metres
what is frequency of a wave
number of wavelengths passing a single fixed point in one sec
number of cycles per sec
what unit is frequency of a wave measured in
hertz
what is equation for velocity of wave
v = fλ
what is amplitude
maximum displacement of particle from equilibrium point
can amplitude be negative
no, its always positive
what is intensity of wave
square of amplitude
what is the period of a wave
number of seconds it takes for one wavelength to pass a fixed point
what is frequency relationship to period
period is the reciprocal of frequency
T = 1/f
what does it mean when waves are phase with eachother
2 waves begin at the same point and have the same wavelength
what is interference
superimposition of waves to create a new wave
what are the 2 types of interference
constructive and destructive
what is constructive interference
add together to create wave with a larger displacement than either original wave
what is destructive interference
waves add together to create a wave with smaller displacement than either original wave
what is resonance
when waves cause a object to vibrate at one of its natural frequency
when does resonance occur
when first object is vibrating at the natural frequency of the second object
what produces standing waves
produced from the repeated interference of 2 waves of identical frequency moving in opposite directions along the same medium
what standing waves consist of which 2 things
nodes and antinodes
what do nodes result from
destructive interference of the 2 waves
what are nodes in terms of displacement
points of no displacement
what causes antinodes
constructive interference of the 2 waves
what are antinodes in terms of displacement
maximum displacement from rest position
what are harmonic series
list of all wavelengths from largest to smallest of possible standing waves
how are harmonics numbered
from longest to shortest wavelength
the first harmonic has how many nodes
2 - the fewest number of nodes
each successive harmonic in the series has what change in # of nodes
extra 1 node
what is periodic motion - what are its 2 characteristics
motion that is regular and repeating
