Fireworks Video

Calculate the distance that the fireworks were away from the observation point. The temperature on the observation night of June 28 was 64°F = 18°C. Using the equation1 for the speed of sound in air of v = 331.3 + 0.6T m/s where T is the temperature in degrees Celcius yields
v = 331.3 + 0.6(18) = 342 m/s

Measure the time delay in the video between when you see the explosion and when you hear the explosion. Since the speed that sound travels in air is known (from above) the distance to the explosion can be found from the equation
d = vt
Make at least 5 time measurements and find the average time.


  1. What is the average time that you found?
  2. What is the distance to the fireworks explosions?
  3. Why don't you need to worry about how long it takes light to travel this distance?
Fireworks Movie (QuickTime format):
Small (5.4 MB)
Larger (23.2 MB)


1 Rossing, T.D., Wheeler, P., and Moore, R. The Science of Sound, 3rd ed. 2002 Addison Wesley. p. 47