A student measures the speed of sound in air.
She places two microphones in a straight line with a loudspeaker. The microphones are 1.36 m apart. Both microphones are connected to a data logger.
The loudspeaker makes a short click. The data logger records a time difference of 4.0 ms between the click reaching the first microphone and reaching the second microphone.
Calculate the speed of sound in air.
Explain why this method gives a more accurate value than one person using a stopwatch to time the sound over the same distance.
The loudspeaker now makes a continuous note with a frequency of 850 Hz. The microphones are connected to an oscilloscope, which shows the wave detected by each microphone.
The student moves the second microphone further away. The two waves on the oscilloscope go from being in step to being in step again when the distance between the microphones has increased by one wavelength.
Calculate the distance the student moves the second microphone.
52 exam-style questions on OCR GCSE Physics 5.1 Wave behaviour, covering 5.1.1 Describing wave motion, 5.1.2 Wavelength and frequency, 5.1.3 Wave speed, frequency and wavelength, 5.1.4 Wave speed problems, 5.1.5 Transverse and longitudinal waves, 5.1.6 Sound waves crossing between media, 5.1.7 Reflection, transmission and absorption at interfaces, 5.1.8 Sound waves and vibrations in solids, 5.1.9 Frequency range and human hearing, 5.1.10 Modelling waves with water ripples and sound, and 5.1.11 Evidence that the wave travels, not the medium. Each one has a worked solution and a mark scheme showing where the marks go.