waves INTRO autumn test Flashcards
up to and including refraction PMT summary notes
wavelength
wavelength
distance between the same points on two consecutive waves
amplitude
amplitude
distance from equilibrium line to the maximum displacement (crest or trough)
frequency
frequency
number of waves that pass a single point per second
period
period
time taken for a whole wave to completely pass a single point
velocity =
velocity =
velocity = frequency x wavelength
period =
period =
period = 1/ frequency
increase frequency…
increase frequency…
velocity increase
wavelength increases…
wavelength increases…
velocity increases
period is inversely/ directly proportional to frequency?
period is inversely/ directly proportional to frequency?
inversely
smaller period…
smaller period…
higher frequency, greater velocity
transverse waves
Transverse waves
have peaks and troughs
vibrations are at right angles to direction of travel
e.g. light or any electromagnetic wave
longitudinal waves
Longitudinal waves
have compressions and rarefactions
vibrations are in the same direction as the direction of travel
e.g. sound waves
measuring velocity: sound in air
measuring velocity: sound in air
make a noise 50m from a solid wall, record time for the echo to be heard
calc using speed=distance/time
OR
have two microphones connected to a datalogger at a large distance apart, record time difference between a sound passing one to the other
calc using speed = distance/time
measuring velocity: ripples on water surface
measuring velocity: ripples on water surface
use a stroboscope (same frequency as water waves), measure distance between the ‘fixed rippes’
calc using wave speed=frequency x wavelength
OR
move a pnecil along the paper at the same speed as a wavefront, measure the time taken to draw this line
calc using speed=distance/time
waves can be…
waves can be…
refracted, reflected, absorbed or transmitted
