Waves Flashcards
What are waves?
Waves transfer energy and information from one place to another using vibrations, but they do not transfer matter in the direction they are travelling.
What is wavelength?
The wavelength (in metres) of a wave is the distance the wave travels in one complete cycle - the distance between two adjacent peaks or two adjacent troughs.
What is amplitude?
The amplitude (in metres) of a wave is the maximum displacement of a wave. It is measured from the top of a peak to the centre line, or from the bottom of a crest to the centre line.
What are the two waves of calculating the speed of a wave?
- speed of a wave (m/s) = distance travelled (m) / time taken (s) or v = x/t
- speed of a wave (m/) = frequency (Hz) x wavelength (m) or v = f x (wavelength symbol).
How do you calculate the wavelength?
wavelength = speed/frequency
What are transverse waves?
In transverse waves, the vibration is at right angles to the direction of wave travel.
What are longitudinal waves?
In longitudinal waves, the vibration is back and forth along the direction of wave travel.
Give 2 examples of transverse waves:
Electromagnetic waves and water waves are transverse waves.
Give an example of longitudinal waves:
Sound waves are longitudinal waves.
How do longitudinal waves travel?
Longitudinal waves such as sound waves travel as a series of compressions and rarefactions.
What are seismic waves?
Seismic waves are produced by earthquakes and explosions.
What are the two types of seismic waves?
- Primary (P) waves - these are slower-moving longitudinal waves
- Secondary (S) waves - these are faster-moving transverse waves.
How are seismic waves detected?
Seismic waves are detected using a seismograph or seismometer.
What are the vibration of the Earth’s surface recorded by?
The vibration of the Earth’s surface is recorded by its motion relative to a heavy pendulum.
