Recall that waves transfer energy and information without transferring matter
Recall that waves transfer energy and information without transferring matter
Explain how waves will be refracted at a boundary in terms of the change of direction and speed
Recall that different substances may absorb, transmit, refract or reflect waves in ways that vary with wavelength
**Describe the processes which convert wave disturbances between sound waves and vibrations in solids, and
a) explain why such processes only work over a limited frequency range b) use this to explain the way the human ear works**
Recall that sound with frequencies greater than 20,000 hertz, Hz, is known as ultrasound
Recall that sound with frequencies less than 20 hertz, Hz, is known as infrasound
**Explain uses of ultrasound and infrasound, including
a) sonar b) foetal scanning c) exploration of the Earth’s core**
Describe how changes, if any, in velocity, frequency and wavelength, in the transmission of sound waves from one medium to another are inter-related
Core Practical: Investigate the suitability of equipment to measure the speed, frequency and wavelength of a wave in a solid and a fluid
Describe evidence that with water and sound waves it is the wave and not the water or air itself that travels
Define and use the terms frequency and wavelength as applied to waves
Use the terms amplitude, period, wave velocity and wavefront as applied to waves
Describe the difference between longitudinal and transverse waves by referring to sound, electromagnetic, seismic and water waves
Recall and use both the equations below for all waves:
wave speed (metre/second, m/s) = frequency (hertz, Hz) × wavelength (metre, m)
wave speed (metre/second, m/s) = distance (metre, m) ÷ time (second, s)
Describe how to measure the velocity of sound in air and ripples on water surfaces
Calculate depth or distance from time and wave velocity
Describe the effects of:
a) reflection b) refraction c) transmission d) absorption
of waves at material interfaces