Lightning!

Greetings Science English students! I hope you're having a good week. This week's topic is an interesting and somewhat scary topic and one that everyone grows accustomed to from childhood - lightning. Lightning accompanies thunderstorms with strong winds. Lightning is basically a discharge of electricity, or a giant spark. Sparks like this happen within one cloud, from one cloud to the other, or from a cloud to the ground. Each lightning stroke heats the air to an amazing 30,000 degrees  C. The heat rush causes the air to expand in an explosion, and this explosion causes a shockwave that becomes a booming sound - one we call thunder. Thunder travels from the lightning source outwards in all directions. This is why we always see lightning and hear thunder together. Light travels fast and so we see lightning immediately, but sounds waves travel more slowly, and it takes longer for thunder to reach our ears. As a child, I remember my father telling me that you could determine how far away the thunderstorm is by counting right after we see lightning. Thunder sound travels 1 km in 3 seconds, so if we count 1 Mississippi, 2 Mississippi, 3 Mississippi (the approximate time to count one second) then we know the lightning has traveled 1 km. If we can count up to 15 seconds, we know the thunderstorm is 3 km away. If the lightning stroke is very close to us, we hear a loud crack and then a loud bang. A rumbling sound indicates that a storm is farther away. What causes lightning? We really don't know. However, on condition for lightning to occur is that there must be separate regions containing opposite electrical charges. Let's learn more in the upcoming class! See you next time.