Chapter 15 test cards Flashcards
What is a wave?
A disturbance that transfers energy from place to place
What waves require a medium to travel through?
Mechanical waves
Which waves move the medium in a direction perpendicular to the direction in which the waves are traveling?
Transverse waves
What is the highest part on a transverse wave called?
Crests
What is the lowest part of a transverse wave called?
Troughs
Which waves move the particles of the medium parallel to the direction in which the waves are traveling?
Longitudinal waves
True or False
Longitudinal waves look like a spring.
True
In a longitudinal wave, the parts where the coils are close together are called what?
Compressions
The parts of longitudinal waves where the coils are spread out are called what?
Rarefactions
What are the basic properties of waves?
Amplitude, wavelength, frequency and speed
What is amplitude?
The maximum distance the particles of the medium carrying the wave move away from their rest positions.
How can you find amplitude?
By measuring the distance from the rest positions to ta crest or trough
The distance between two troughs or two crests of a transverse wave is called what?
The wavelength
What’s the formula for speed?
Speed = Wavelength x Frequency
What’s the formula for frequency?
Frequency = Speed / Wavelength
What’s the formula for wavelength?
Wavelength = Speed / Frequency
True or False
When an object or wave hits a surface through which it cannot pass, it travels around it.
False (it bounces back)
What is it called when a wave hits a surface through which it cannot pass and the wave bounces back?
Reflection
What is an example of an echo?
The reflection of a wave
State the Law of Reflection
The law of reflection - The angle of incidence equals the angle of reflection
What is the bending of wave called?
Diffraction
True or False
When a wave moves around a barrier or through an opening in a barrier, it bends and spreads out.
True
What is it called when two waves meet?
Interference
What is a constructive interference?
When two waves combine to make a wave with a larger amplitude
What is a destructive interference?
When the amplitudes of two waves combine
True or false
In a standing wave, destructive interference produces points with an amplitude of 9
False
What are points with an amplitude of 0 called?
Nodes
Waves produced by earthquakes are called what?
Seismic waves
What are the 3 kinds of seismic waves?
P waves, S waves, and surface waves
What is a surface wave?
A combination of a longitudinal wave and transverse wave that travels along the surface of a medium
Which wave arrivals at seismographs first?
P waves
What are P waves?
Longitudinal seismic waves that can travel through earth
What are S waves?
Transverse seismic waves that cannot travel through liquids
How can scientists tell how far away an earthquake was?
By measuring the time between the arrival of P waves and the arrival of S waves
