I know the number of seconds between the two can be used to estimate how far away the lightning is – but what’s the scale, here? One second = what fraction of a mile?
One Second = 1,116.4 feet = roughly 1/5th of a mile.
Thanks!
Or if you want to do it in metric, 1 second = 330m, or about 1/3 of a kilometer.
Sorta. The speed of sound is dependent on the temperature, so it can vary from about 1087.4 ft/s at 0 C to 1145.6 ft/s at 30 C.
Well, given the incredible precision of the timing device (me mentally counting “One Mississippi, two Mississippi…”), I’m not sure we necessarily need to factor that in.
Not at all. 5 seconds = 1 mile is a good first-order approximation. I was just clarifying the point that the speed of sound is not a fixed value.
It was my impression that Q.E.D. was simply noting the fact that the supposed equality of “One Second = 1,116.4 feet” is actually temperature dependent, and that reporting this equality to five significant figures with no mention of this gives a false sense of precision.
Sorry, I should have added a smiley of some sort – I just meant ballpark was all I was after.
Has anyone watched any lightning stroke and then guessed how it would sound before it reached you? Kind of trying to make a 3D “audioization” from a 3D visualization, by judging the distance of the entire stroke from you and figure if it’s gonna boom or rumble depending on your position w.r.t. the entire stroke.
The speed of sound in the ballpark is essentially the same as other places nearby. 
But the game is usually postponed during inclement weather, anyway. I’m confused.
