How far away is the storm?

[dot.hawkes]

since I was little , i have always counted from when the lightening flashed to when the thunder rolled, and the number i got to was how far away the storm was in miles, so if i counted to 10 it was 10 miles away. how scientifically accurate is this method.?

[mibn2cweus]

If this doesn't tell you what you want to know, please ask for details . . . Thunder & Lightning

[dot.hawkes]

drestie showed me that klink last night but i still did not fully grasp why the counting method is now suddenly not accurate after having known about it an used it for nearly 50 years.

[sddsddean]

Sound travels at (about) 700mph at sea level. Thats 11 2/3 miles per minute or 0.194 miles per second. Therefore in 5 seconds it will travel near enough 1 mile. So, you see the flash, count in seconds 'til you hear the thunder, divide by 5 and thats how many miles away the lightning bolt was /storm is.

[drestie]

Thanks everyone - she just wouldn't believe me :)

[mibn2cweus]

Try the following demonstration:

Find a dark spot where you have measured off a distance of one-mile. At the other end of this distance have someone light a loud bright fire-cracker. This effect can also be measured when observing a fire-works display provided they are dispersed in time enough to distinguish which boom came from which explosion (flash). (Proving the speed of light may will require a little more technology).

Anyone else have any bright ideas?