A pulse is sent vertically down through water. An echo from a fish arrives after 0.040 s and an echo from the seabed arrives after 0.160 s. Sound travels at 1500 m/s. How far above the seabed is the fish?
180 m180\ \mathrm{m}180 m
30 m30\ \mathrm{m}30 m
120 m120\ \mathrm{m}120 m
90 m90\ \mathrm{m}90 m
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.