Electrostatics
The lightning Theif by: Dallas Rodin
Electrostatics in Lightning
On those musty and livid days, where nothing but massive storm clouds are seen, we experience one of the most fascinating but alarming creations. This so called mystery light that happens to appear and disappear with a blink of an eye is called lightning. Lightning may be seen during a short period of time, but the cycle of how it starts is a long process. It starts with an electrical storm which is a thunderstorm or other violent disturbance of the electrical condition of the atmosphere.
An iron rod being placed on the outside of a building from the highest part continued down into the moist earth, in any direction strait or crooked, following the form of the roof or other parts of the building, will receive the lightning at its upper end, attracting it so as to prevent it's striking any other part; and, affording it a good conveyance into the earth, will prevent its damaging any part of the building.
These storm clouds are charged, with the topmost part of the cloud being positive, leaving all negatively charged electrons at the bottommost portion of the cloud. To form this kind of separation between the two subatomic particles we must first understand one of the most important keys in Earth’s environment, the water cycle. During the day, bodies of water on earth’s surface absorb and collect the heat from the sun. Once this is done, some liquid molecules will contain enough energy to break out and advance into the earth’s atmosphere in a process called evaporation.
As these water droplets rise upward, the clouds are already known to have their millions of water droplets whirling and spinning around in a destructive manner. As the evaporating water molecules increase in height they begin to conflict with the molecules within the clouds. The electrons within the rising molecules are split away from their original atom and reconnect within the bottom half of the cloud, thus creating a negative charge in this area. This process is called a charge separation. This increase of static charge in the cloud causes its electric field to become stronger and stronger.
How lightning works
The more powerful build up in electrons at the bottom of the cloud causes the electrons to attract to the protons of another cloud or the ground. By attracting the protons on the ground, this leads to an extraordinary amount of discharge of electrons in the clouds, which is known to create the ground strike of lightning. A lightning bolt occurs when these electrons travel up to 60 miles per second towards the protons near earth's surface. As the lightning bolt grows closer and closer towards the ground the electrons in the bolt drive the electrons on the surface to move farther and farther away, creating a positively charged area. This causes protons from the earth's surface to rise upwards into such things like trees, buildings and people. This process is called a streamer. Once the streamer meets the "step leader" or the descending cloud electrons, a pathway is produced and lightning finally begins.
Citations
Zavisa, John. "How Lightning Works" 01 April 2000. HowStuffWorks.com. <http://science.howstuffworks.com/nature/natural-disasters/lightning.htm> 12 February 2013.
Static Electricity. The Physics Classroom, 2012. Web. 12 Feb. 2012
Wagon, Joy. Lightning Physics. Joy Wagon, 1999. Web. 12 Feb. 2012