In Olympic competition, a microphone detects the sound of the starters gun and sends it electrically to speakers at every runners starting block. Why?
Solution 12E Step 1: Suppose there are 10 runners for a race standing with 1 m distance between each. Suppose, the starters gun is kept 5 metres apart from the track as explained in figure 1. The sound from the starters gun should travel a maximum distance of 14 metres. Speed of sound in air, v = 340 m/s The required for the sound to travel 14 metres would be, t = 14 m / 340 m/s = 0.04 seconds. The sound of the gun will be reached to the last person only after 0.04 seconds. The time required for the sound to travel 5 metres would be, t = 5 m / 340 m/s = 0.01 seconds The sound of the gun will be reached to the first person after 0.01 seconds. But, in a race, the starting time will affect the results. In order to overcome this issue of lag in sound, they are using electrical speakers to every starting block. Conclusion: Electrical speakers are used in a race in order to overcome the issue of time lag in the sound.