During a cave survey, a sound transmitter and detector are placed together. A pulse reflected from a rock column returns to the detector after 0.030 s. The back wall of the cave is 5.1 m farther from the detector than the rock column. Sound travels at 340 m/s. How long after the pulse is transmitted does the echo from the back wall return?
0.045 s0.045\ \mathrm{s}0.045 s
0.015 s0.015\ \mathrm{s}0.015 s
0.090 s0.090\ \mathrm{s}0.090 s
0.060 s0.060\ \mathrm{s}0.060 s
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.