Visible loud event
- Get 2 people who will be standing 200 to 300 metres apart in a large open space as such they can see each other.
- One person will be responsible for creating a visible loud event like banging a drum.
- The other person will time the difference between seeing that event and hearing that event using a stopwatch.
- Repeat this 3 times and average out the time it takes the sound the travel 200 metres.
- Use the formula speed = distance/time to calculate the speed of sound in air