Heat-resistant ceramic tiles line the inside of a furnace. An ultrasonic probe is placed against the exposed surface of a tile. The probe records the time between sending a pulse and receiving its reflection from the rear surface.
A reference tile made from the same ceramic is used to calibrate the probe.
| measurement | tile thickness / mm\text{mm}mm | echo time / μs\mu\text{s}μs |
|---|---|---|
| reference tile | 20.0 | 12.5 |
| tile being inspected | unknown | 9.6 |
The tile being inspected was 18.0 mm thick when it was installed.
Calculate the current thickness of the tile being inspected in mm\text{mm}mm.
The maintenance team wants to use the echo time to decide whether a tile needs replacing. A tile must be replaced when its thickness is less than 88% of its installed thickness.
Determine whether the tile being inspected must be replaced. Use the measurements to support your answer.
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.