Coastal engineers are investigating a regular train of surface waves produced by a test boat in a marina. Two marker posts can be positioned along the direction in which the wave crests travel. The engineers have a long measuring tape and a video camera that records both posts at a known frame rate.
At a rail maintenance depot, engineers are testing a straight section of steel rail before it is installed. The rail is securely supported. They have a vibration generator connected to a signal generator, a movable pickup connected to an oscilloscope, and a tape measure.
Explain how each investigation should be carried out so that the recorded quantities lead to a reliable value for wave speed. Your answer should justify the use of video at the marina and of electronic detection on the rail.
112 exam-style questions on Edexcel GCSE Physics 4.1 Wave properties, covering 4.1.1 Waves transfer energy and information, 4.1.2 Frequency, wavelength, amplitude, period and wavefronts, 4.1.3 Longitudinal and transverse waves, 4.1.4 The wave speed equations, 4.1.5 Measuring wave velocity, and 4.1.6 Calculating depth or distance from waves. Each one has a worked solution and a mark scheme showing where the marks go.