A student wants to determine the speed of sound in air by measuring the time delay of an echo from a tall, flat wall. She stands at a distance d d\,d from the wall and claps two wooden blocks together. She measures the time interval t t\,t between making the clap and hearing the reflected sound.
Which type of sound should she make, and which formula should she use to calculate the speed of sound, vvv?
Type of sound: a continuous whistle; Formula: v=dtv = \frac{d}{t}v=td
Type of sound: a continuous whistle; Formula: v=2dtv = \frac{2d}{t}v=t2d
Type of sound: a single sharp clap; Formula: v=2dtv = \frac{2d}{t}v=t2d
Type of sound: a single sharp clap; Formula: v=d2tv = \frac{d}{2t}v=2td
295 exam-style questions on CIE IGCSE Physics Sound, covering Sound. Each one has a worked solution and a mark scheme showing where the marks go.