During a school sports day, a 170 m170\text{ m}170 m race is held. A starter at the beginning of the track fires a starting pistol, and a timekeeper stands at the finish line, 170 m170\text{ m}170 m away.
Sound travels through the air at 340 m/s340\text{ m/s}340 m/s. Calculate the time taken for the sound from the starting pistol to reach the timekeeper.
The timekeeper takes 0.15 s0.15\text{ s}0.15 s to react after hearing the sound, and then starts the stopwatch. He makes no other experimental inaccuracies.
By how much will the recorded time for the race be in error?
Suggest how the timekeeper can reduce this error, whilst still using the same stopwatch.
When the timekeeper stops the stopwatch as the winner crosses the finishing line, the stopwatch displays an elapsed time of 18.40 s18.40\text{ s}18.40 s. Calculate how long the winner actually took to run the race.
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.