I always thought that after you saw the lightening, you counted seconds until you heard the thunder. Then the storm would be that many miles away. Yet, on Extreme Survival yesterday Bear Grills was on the American plains and there was a nasty storm approaching. He counted six seconds and said that it meant the storm was only 1 mile away! Have i been wrong all this time, or is Bear wrong?
From Wikipedia
'The speed of sound is the distance travelled during a unit of time by a sound wave propagating through an elastic medium. In dry air at 20 °C (68 °F), the speed of sound is 343.2 metres per second (1,126 ft/s). This is 1,236 kilometres per hour (768 mph), or about one kilometer in three seconds or approximately one mile in five seconds.'