indonesia 2005
DESCRIPTION
Waves. Indian Ocean 2004. Indonesia 2005. Waves. Waves are everywhere in nature – sound waves, visible light waves, earthquakes, water waves, microwaves…. What do you know about waves?. Longitudinal Waves. - PowerPoint PPT PresentationTRANSCRIPT
Indonesia 2005
Indian Ocean 2004
Waves
Waves are everywhere in nature – sound waves, visible light waves, earthquakes, water waves, microwaves…
Waves
What do you know about waves?
Longitudinal Waves
In this type of wave, particles vibrate back and forwards along the direction the wave is
travelling.
Transverse Waves
This type of wave moves perpendicular to the motion of the particle
Standing Waves
Maybe you've noticed or maybe you haven't. Sometimes when you vibrate a string, or cord, or chain, or cable it's possible to get it to vibrate in a manner such that you're generating a wave, but the wave doesn't propagate. It just sits there vibrating up and down in place. These are called standing waves.
These specialized waves have places where the medium does not vibrate at all, called nodes, and other places where the medium vibrates the most, called antinodes. Standing waves have a changing numbers of nodes and antinodes.
Properties of WavesWhat is meant by the axis of a wave?
The axis is the line runningthrough the middle of thewave pattern.
What is meant by the crest of the wave?
The crest is the top part of the wave
…and the trough?
The trough is the bottompart of the wave.
What is the amplitude of the wave?
The amplitude is thedistance from the axis tothe crest
or from axis to trough.
Definition of Wavelength?The wavelength is thedistance after which thewave pattern repeats itself– the distance between twoidentical points on the wave
Wavelength is given
the symbol λ pronounced lambda.
FrequencyThe frequency of the wave is the
number of waves each second.
It is measured in hertz (Hz) which justmeans “per second”.
Period
The period of a wave is the time takenfor one complete wave to pass a point.
It is measured in seconds (s).
Frequency
The link between the frequency andperiod of a wave
Tf 1
Period
Rearrange to find period
T= nn=cycles f
Draw a WavePosition/Amplitude = 6cmPeriod = 2s
Position/Amplitude = 5cmPeriod = 6s
Position/Amplitude = 12cmPeriod = 10s
Position/Amplitude = 4cmPeriod = 8s
