Longitudinal and Transverse Waves

What do Waves do?

When waves travel through a medium, the particles vibrate and transfer energy and information from one place to another (but they don’t transfer matter)

In displacement-distance graphs; Distance

How far the wave has travelled from its starting point

Displacement

How far from the equilibrium point thr wave has oscillated

Wavelength

Distance of one entire oscillation:

1) from equilibrium>up>down>back up

2) from top of the wave(crest)>down>back up to the next crest

Crest

Top of a wave

Trough

Bottom of the wave

Amplitude

Maximum displacement of a point of a wave from its rest position

In displacement-time Graphs; time period

time it takes for one complete oscillation

Frequency equation

Frequency=1/time period

Frequency

Number of complete oscillations per second (Hertz/Hz)

Wave speed equation

Wave speed (m/s) =frequency(Hz) × wavelength(m)

Or

Wave speed (m/s) = Distance travelled by wave (m) / time taken (s)

Transverse waves

Oscillations are perpendicular to the direction of energy transfer(the direction in which the wave is moving)

1) vibrations are going up and down

2) overall wave travelling from left to right

Examples of transverse waves

1) Electromagnetic waves(light, radiowaves)

2) ripples/waves in water

3) waves of strings (guitar)

Longitudinal waves

Oscillations are parallel to the direction of energy transfer

1) some regions are more spread out (rarefactions - low pressure, fewer particles)

2) some regions are more compressed (compressions - high pressure, lots of particles)

Examples if longitudinal waves

1) sound waves

2) seismic P waves