If a lightning occurred exactly 1 mile from your location, how many seconds will it take for the sound waves created by the thunder to reach your  ears at 343 m/s?

5 seconds

Explanation:

sound travels 1 km in roughly 3 secs so 1 mile in roughly 5 secs.

r=rho l/a where a is the area, l is the length and rho is resistivity so the greater the area the lesser the resistance thats why the earth pin is thicker bcos current follow the shortest path, so less resistive .