A student determines the speed of sound in air using an echo method. They stand a distance d d\,d from a large vertical wall and clap two wooden blocks together at a steady rate so that each clap coincides exactly with the echo of the previous clap. They use a stopwatch to measure the total time t t\,t for 20 successive claps.
Which of the following modifications to this experimental procedure would most effectively improve the accuracy of the calculated speed of sound?
Decrease the distance ddd between the student and the wall.
Measure the total time taken for 50 successive claps rather than 20.
Use an analogue stopwatch with a lower resolution of 0.5 s0.5\text{ s}0.5 s.
Stand closer to the wall and make quieter claps.
64 exam-style questions on Edexcel GCSE Physics 4.1 Wave properties. Each one has a worked solution and a mark scheme showing where the marks go.