is it true that if you see lightening, then count in seconds until you hear thunder, that's how far the storm would be in miles? and if so, how do you know in what direction?
2007-06-15 03:02:59 · 8 answers · asked by roy s 2 in Science & Mathematics ➔ Weather
You need to count the number of seconds and then divide by 5 to get the number of miles.
Sound travels at 340 metres per second, about 770 miles per hour or about one mile every 5 seconds.
What you hear as thunder is basically a sonic boom. The lightning stroke heats the air surrounding is causing it to expand very rapidly then contract again. This happens so fast that the movement of the air exceeds the sound barrier causing a sonic boom.
A stroke of lightning is often several kilometres long and although it occurs in an instant the sound doesn't reach you all at once - you hear the sound from the nearest part of the lightning stroke first then the rumbling sound as the rest of the sound reaches you over the next few seconds.
Because a lightning storm often causes many strokes of lightning in many locations it's not really possible to say how far the storm is, just how far a particular stroke of lightning is. The centre of the strom could be directly overhead but lightning could be striking many miles away.
As for the direction, you just have to use your eyes and ears and look and listen where the lightning is.
2007-06-15 03:08:01 · answer #1 · answered by Trevor 7 · 1⤊ 0⤋
Sound travels at around 1000 feet/second. Light travels so fast that you see the lightning instantaneously. There are 5280 feet in a mile, so count the seconds between the lightning and thunder and divide by five to get the approximate distance in miles. The direction is the direction of the lightning flash.
2007-06-15 10:16:59 · answer #2 · answered by rj1220a 2 · 0⤊ 0⤋
Count for 5 seconds = 1 mile
The speed of sound in air is about 1/5 th of a mile, so if you count for 5 seconds, that is one mile.
30 seconds is 5 miles, which is close enough to get inside.
The direction is in the direction in which you see the flash of the lightning.
If too cloudy and you don't see the flash, it is hard to say which direction.
2007-06-15 10:07:50 · answer #3 · answered by zippythewonderslugohio 4 · 2⤊ 0⤋
I heard very recently on a weather program on TV that every five seconds between lightning flash and thunder rumble equals one mile distance. For direction, you'll just have to look to see where the lightning flashed.
If flash and "crash" happens simultaneously, be thankful. You just survived a lightning strike!!!
Our across the road neighbor's tree got nailed that way a number of years ago. It sounded like a bomb went off in our house. SCARY!!!!
2007-06-15 10:13:31 · answer #4 · answered by SallyJM 5 · 0⤊ 0⤋
the storm, unless its already there...is coming from the direction the wind is blowing...and although the 1/5 of a mile per second is correct, its not that accurate. the speed at which a storm is moving can drastically change from minute to minute
2007-06-15 10:12:23 · answer #5 · answered by RSbear007 2 · 0⤊ 0⤋
I think it IS true. I've heard the same thing, but I dont know if there is anyway of telling from where. Why dont you just watch the weather channel, they usually tell you exactly how far it is and where its coming from. Hope I helped a little.
2007-06-15 10:11:28 · answer #6 · answered by Anonymous · 0⤊ 1⤋
like night and day
2007-06-15 10:07:22 · answer #7 · answered by Anonymous · 0⤊ 1⤋
i havent
2007-06-15 10:10:13 · answer #8 · answered by Isabel 2 · 0⤊ 0⤋