Waves Flashcards
what is a wave?
a wave is a vibration/oscillation which transfers energy without transferring any matter by making the particles of substances it is travelling through vibrate
wave diagram
for sound waves what does a high amplitude mean?
high amplitude = loud sound
what does low amplitude mean for sound waves?
low amplitude = quiet sound
what would frequency be for aerobic respiration?
low frequency
what would frequency be for anaerobic respiration?
high frequency
What is frequency?
the number of complete waves passing a certain point every second
what is frequency measured in?
Hertz - Hz
What is period (time) for waves?
the time it takes for one complete wave to pass
how to calculate period?
p (time in seconds) = 1/f (frequency in hertz)
how to calculate speed?
v (speed in m/s) = λ (wavelength in m) × f (frequency in hertz)
what is a transverse wave?
waves in which the vibrations go 90° to the direction of energy transfer of the wave eg. EM waves.
what is a longitudinal wave?
waves in which the vibration is parallel to the direction of energy transfer
electromagnetic spectrum
gamma rays uses
radiotherapy cancer treatment:
-destroys cancer cells
-needs correct does
-precise area
Irradiation
-food stays fresher
x-rays uses
detect broken bone:
-absorbed by bones (white parts)
-easily pass through skin/tissue (black parts)
UV ray uses
tanning
detecting hidden marks:
-mark items with UV pen (invisible ink)
-shine UV
-ink absorbs UV and reflects visible light
microwave uses
heating food:
-absorbs by water molecules
-molecules vibrate —> heat energy
satellite signals:
-easily pass through atmosphere
what are things that happen to waves when they reach a boundary?
-absorbed (material becomes hot)
-reflect (mirror)
-transmit (pass through)
-refracts (bends)
why does refraction happen?
when waves change speed and direction when passing from one medium to another eg. from air to water
refraction diagram
wavy water surface
diffused reflections as wave is hitting wavy surface at different angles
