P12 - Wave Properties Flashcards
name:
both types of wave
transverse and longitudinal
define:
transverse wave
direction of oscillation is perpindicular to direction of energy transfer
define:
longitudinal wave
direction of oscillation is parallel to direction of energy transfer
what does a wave transfer
waves transfer energy, not matter
define:
amplitude
of waves
disturbance from rest
height of the wave at a specific point
define:
wavelength
distance from a point on a wave to the equivalent point on the adjacent wave
properties:
transverse wave
- perpendicular oscillation
- travels at speed of light in a vacuum
properties:
longitudinal wave
- parallel oscillation
- due to compressed particles
- compressions and rarefactions
define:
frequency
number of waves passing a fixed point per second
define:
periodicity
amount of time it takes for one wave to pass a fixed point
formula:
linking frequency and periodicity
frequency = 1 / periodicity
formula:
wave speed
wave speed = freqency * wavelength
v = fλ
What is frequency measured in?
Hertz (Hz)
Where do earthquakes occur?
conservative plate boundaries
explain:
How is magnitude measured?
a seismomenter is used, magnitude is measured on the richter scale
2 properties:
Primary waves
- moves through solid rock and fluid
- longitudinal (pushes and pulls rock)
2 properties:
Secondary waves
- only moves through solid rock
- transverse
define:
shadow zone
the area on the Earth’s surface where P or S waves cannot be detected
What are shadow zones used for?
determining the inner structure of the Earth
list:
layers of the Earth
- crust
- mantle
- outer core
- inner core
define:
constructive interference
waves in phase which add up amplidtudes (amplification)
define:
destructive interference
waves out of phase which cancel each other out
list 3:
required practicals for investigating wavelength
- vibration generator
- ruben’s tube
- wave generator
What frequency is ultrasound
ultrasound > 20 000Hz
Limit of human hearing
20Hz - 20 000Hz
list 3:
uses of ultrasound
- echolocation
- Sonar
- pregnancy scans
explain:
How does range finding work?
Timing how long it takes for a wave to be emitted, reflected off a surface and then reabsorbed.
How is sound heard by the ear?
- pinna collects sound waves
- waves travel through ear canal
- ear drum vibrates
- ossicles (bones) amplifty the vibrations
- cochlea converts pressure waves to electrical sound
- auditorial nerve carries it to the brain
