Table 1 shows the height of a cavern ceiling, measured using ultrasound pulses, at various horizontal distances from the cave entrance.
| Distance from cave entrance (m) | Height of cavern ceiling (m) |
|---|---|
| 0 | 5.2 |
| 15 | 9.8 |
| 30 | 14.5 |
| 45 | 19.0 |
| 60 | 23.5 |
| 75 | 27.2 |
| 90 | 31.0 |
| 105 | 33.8 |
A speleologist uses an ultrasound rangefinder to measure the height of the cavern ceiling when they are positioned exactly 75 m from the cave entrance.
Calculate the total round-trip travel time of the ultrasound pulse for this measurement.
The speed of the ultrasound pulse in the cave air is 340 m/s.
35 exam-style questions on Edexcel GCSE Physics 4.3 Sound, ultrasound and infrasound, covering 4.3.1 Sound waves, vibrations and the human ear, 4.3.2 Ultrasound and infrasound, 4.3.3 Uses of ultrasound and infrasound, and 4.3.4 Sound waves passing between media. Each one has a worked solution and a mark scheme showing where the marks go.