A manufacturer tests two wave-monitoring systems.
The first system uses a camera to record straight wavefronts in a shallow-water channel. The wave generator operates at 10 Hz.
| Camera measurement | Distance across 6 wavelengths in m\text{m}m |
|---|---|
| 1 | 0.120 |
| 2 | 0.126 |
| 3 | 0.123 |
The second system uses two electronic pickups attached to a steel rail. A vibration pulse travels along the rail from the first pickup to the second pickup.
| Measurement | Result |
|---|---|
| Distance between pickups | 1.50 m |
| Time delay, test 1 | 0.30 ms |
| Time delay, test 2 | 0.31 ms |
| Time delay, test 3 | 0.29 ms |
An installer suggests using a metre rule and a handheld stopwatch to check the systems. A wavefront would be timed across 0.50 m of the water channel. A vibration pulse would be timed across 2.00 m of the rail.
Explain whether handheld timing could provide a useful check of each monitoring system.
Use the measurements to determine both wave speeds and predict the time taken for each wave to travel across the proposed distance.
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.