PhysicsCode 5054
General properties of waves
What this topic asks you to be able to do
- Know that the transfer of energy by waves happens without any transfer of matter
- Describe what wave motion means, using the examples of ropes and springs that vibrate and experiments with water waves
- Describe a wave's characteristics by reference to wavefront, wavelength, frequency, crest (peak), trough, amplitude and wave speed
- Define these terms: (a) frequency, the number of wavelengths passing a given point in each unit of time (b) wavelength, the distance from one point on a wave to the next identical point, such as from one crest to the next (c) amplitude, the greatest distance from the mean position
- Recall wave speed = frequency × wavelength, written v = f λ, and use this equation
- Know that in a transverse wave the vibrations are at right angles to the direction in which energy is transferred, and give examples such as electromagnetic radiation, water-surface waves and seismic S-waves (secondary)
- Understand that in a longitudinal wave the vibration is parallel to the direction in which energy is transferred, and state examples such as sound waves and seismic P-waves (primary)
- Describe the ways in which waves may be subject to: (a) reflection off a plane surface (b) refraction caused by a change in speed (c) diffraction when passing through a gap
- Outline the influence that wavelength and the size of a gap have on diffraction through that gap
- Describe how a ripple tank can be used to show: (a) waves reflecting off a plane surface (b) waves refracting where a change in depth changes their speed (c) waves diffracting through a gap (d) waves diffracting at an edge
- Outline the effect that wavelength has on diffraction at an edge