Wave Basics
What is a wave?
A disturbance that transfers energy from place to place
What are transverse waves?
Waves that move the medium at right angles to the direction the waves travel
What is amplitude?
The maximum distance particles move from their rest position
What is reflection?
When a wave bounces off a surface
What are seismic waves?
Waves produced by earthquakes
What is energy?
The ability to do work
What are longitudinal waves?
Waves that move the particles of the medium parallel to the wave’s direction
What is wavelength?
The distance between two corresponding parts of a wave
What is refraction?
The bending of waves due to a change in speed
What are primary waves (P waves)?
Longitudinal seismic waves
What is a medium?
The material through which a wave travels
What are compressions and rarefactions?
Compressions: coils close together; Rarefactions: coils spread out
What is frequency and what unit measures it?
Frequency is the number of complete waves per second, measured in hertz (Hz)
What is diffraction?
The bending of waves around the edge of a barrier
What are secondary waves (S waves)?
Transverse seismic waves
What are mechanical waves?
Waves that require a medium through which to travel
What are surface waves?
Combinations of transverse and longitudinal waves
What is the equation for speed?
Speed = Wavelength × Frequency
What is interference?
When two or more waves meet and affect each other
What are tsunamis?
Huge surface waves caused by underwater earthquakes
What is vibration?
A repeated back and forth or up and down motion
What are the crest and trough of a wave?
Crest: highest part; Trough: lowest part
If frequency increases and speed stays the same, what happens to wavelength?
Wavelength decreases
Explain constructive vs. destructive interference.
Constructive: combine for larger amplitude; Destructive: combine for smaller amplitude
How do seismographs help scientists locate earthquakes?
They record P and S waves, helping scientists calculate distance and pinpoint the epicenter and time of the earthquake