A pulse travels through 12 m of water at 1500 m/s and then through 18 m of sediment at 3000 m/s. It reflects and returns along the same path. What is the total travel time?
28 ms28\ \mathrm{ms}28 ms
20 ms20\ \mathrm{ms}20 ms
40 ms40\ \mathrm{ms}40 ms
14 ms14\ \mathrm{ms}14 ms
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.