Question

If 5sec, is the elapsed time between a lightning flash and a thunder, how far away is the storm ?

Answer 1

Hint:- Generally , the distance between any two points is calculated when time and speed are given to us using the formula :
Distance =speed $\times$ time
Speed of sound in air is taken as 345m/s.

Complete step-by-step solution :
Let's discuss lightning ,thunder and storm first.
Lightning : Lightning is a naturally occurring electrostatic discharge phenomenon during which two electrically charged regions in the atmosphere, sky or ground temporarily equalize themselves , causing the instantaneous release of as much as around one gigajoule of energy.
Thunder : Thunder is the sound by lightning .Sudden increase in pressure and temperature from lightning produces rapid expansion of the air within and surrounding the path of a lightning strike. expansion of air creates sonic shock waves ,often referred to as a “thunder clap” or “peal of thunder “.
Storm: storm is a meteorological phenomenon in which there is heavy rain, and wind due to moisture in the air occurs. Hail and lightning are also common in storms .Tornadoes are likely to occur during storms.
Lets calculate the distance of storm :
We are given speed of sound and time of lightning so,
$D = S \times T \\\ D = 345 \times 5 \\\ D = 1725m \\\ D = 1.725Km \\\$ (D is the distance,T is the time, S is the speed ) (1Km=1000m).
Storm is 1.725Km away when thunder and lightning has a 5 sec time lapse.

Note:- We have noticed that lightning always strikes and then thunder sound is heard because light travels faster than sound .When lightning heats the air around it to an incredible temperature as hot as around 54000C,the heated air expands explosively and is heard to us in the form of sound.