Waves
3.1 General wave properties
What it is
- Waves can transfer energy and information without a net motion of the medium
through which they travel.
- They involve vibrations (oscillations)
- Wave diagrams capture a snapshot of the wave.
- Wavefronts highlight the part of a wave that is moving together e.g. sets of peaks of
the wave
- Rays highlight the direction of energy transfer
- Describe what is meant by wave motion as illustrated by vibration in ropes and
springs and by experiments using water waves
- Use the term wavefront
- Wavefronts highlight the part of a wave that is moving together e.g. sets of
peaks of the wave
- Give the meaning of speed, frequency, wavelength and amplitude
Amplitude (A)
- The maximum displacement from the mean position.
, -
Wavelength (λ)
- The length of one complete wave.
Frequency
- The number of oscillations in one second. Measured in Hertz.
- F=1/T
Wave speed (V)
- The speed at which the wave fronts pass a stationary observer.
- Wave speed (m/s) = frequency (Hz) x wavelength (m)
- v = fλ
,Period (T)
- The time taken (in seconds) for one complete oscillation. It is also the time taken for a
complete wave to pass a given point.
- 1/ F
- Distinguish between transverse and longitudinal waves and give suitable examples
Transverse waves
- The oscillations are perpendicular to the direction of energy transfer.
Longitudinal waves
- The oscillations are parallel to the direction of energy transfer.
- Describe how waves can undergo:
, - reflection at a plane surface
-
- the angle of which the ray hits the object is the same as the angle of the ray
that is reflected
- the angle of incidence to the normal us the same for both rays
- refraction due to a change of speed
- When a wave changes speed (normally when entering another medium) it
may refract (change direction)
- occurs when there is a change of speed
- When the waves move into a slower medium, the waves bends towards the
normal
- Waves bends away from the normal when it moves into a faster medium
- The waves do not bend when it hits the normal at 90 degrees as the entire
wave will slow down at once, thus, no refraction occurs
3.1 General wave properties
What it is
- Waves can transfer energy and information without a net motion of the medium
through which they travel.
- They involve vibrations (oscillations)
- Wave diagrams capture a snapshot of the wave.
- Wavefronts highlight the part of a wave that is moving together e.g. sets of peaks of
the wave
- Rays highlight the direction of energy transfer
- Describe what is meant by wave motion as illustrated by vibration in ropes and
springs and by experiments using water waves
- Use the term wavefront
- Wavefronts highlight the part of a wave that is moving together e.g. sets of
peaks of the wave
- Give the meaning of speed, frequency, wavelength and amplitude
Amplitude (A)
- The maximum displacement from the mean position.
, -
Wavelength (λ)
- The length of one complete wave.
Frequency
- The number of oscillations in one second. Measured in Hertz.
- F=1/T
Wave speed (V)
- The speed at which the wave fronts pass a stationary observer.
- Wave speed (m/s) = frequency (Hz) x wavelength (m)
- v = fλ
,Period (T)
- The time taken (in seconds) for one complete oscillation. It is also the time taken for a
complete wave to pass a given point.
- 1/ F
- Distinguish between transverse and longitudinal waves and give suitable examples
Transverse waves
- The oscillations are perpendicular to the direction of energy transfer.
Longitudinal waves
- The oscillations are parallel to the direction of energy transfer.
- Describe how waves can undergo:
, - reflection at a plane surface
-
- the angle of which the ray hits the object is the same as the angle of the ray
that is reflected
- the angle of incidence to the normal us the same for both rays
- refraction due to a change of speed
- When a wave changes speed (normally when entering another medium) it
may refract (change direction)
- occurs when there is a change of speed
- When the waves move into a slower medium, the waves bends towards the
normal
- Waves bends away from the normal when it moves into a faster medium
- The waves do not bend when it hits the normal at 90 degrees as the entire
wave will slow down at once, thus, no refraction occurs
