6.1 Waves in air, fluids and solids Flashcards
what are the two types of waves?
- transverse
- longitudinal
what is a transverse wave?
a wave for which the oscillations are perpendicular to the direction of energy transfer.
what is a longitudal wave?
a wave for which the oscillations are parallel to the direction of energy transfer.
give two examples of transverse waves.
- electromagnetic waves
- seismic s-waves
give two examples of longitudal waves.
- sound waves
- siesmic p-waves
what are the two parts of a longitudinal wave called?
compressions and rarefactions.
what is a wave’s amplitude?
the maximum displacement of a point on a wave from its undisturbed position.
what is wavelength?
- the distance from a point on a wave to the same position on the adjacent wave
- most commonly peak to peak or trough to trough
what is the frequency of a wave?
the number of waves that pass a given point each second.
what is the unit used for frequency?
hertz, Hz
what is meany by a frequency of 200Hx?
200 waves pass a given point each second.
what does a wave transfer?
energy
what is a wave speed?
the speed at which the wave moves or at which energy is transferred through a medium.
what word is used to describe when a wave bounces off a surface?
reflection
how do sound waves travel through a solid?
the particles in the solid vibrate and transfer kinetic energy through the material.
state the equation used to calculate wave speed.
wave speed = frequency x wavelength#
speed (m/s), frequency (Hz), wavelength (m)
what is the frequency range of human hearing?
20 Hz - 20 kHz
(1 kHz = 1000 Hz)
what are ultrasound waves?
waves which have a frequency higher than the upper limit of human hearing (20kHz).
give an example use for ultrasound waves?
medical or industrial imaging.
what natural event causes seismic waves to be produced? what types are produced?
- earthquakes
- they produce both p-waves and s-waves
state a difference between the mediums that p-waves and s-waves can travel through.
- p-waves travel through both solids and liquids
- s-waves only travel through solids (not liquids)
what technique is used to detect objects in deep water and measure water depth?
- echo sounding
- high frequency sound waves are emitted, reflected and detected
- time difference between emission and detection, alongside wave speed, are used to calculate distances
