What is a spark? How is lightning formed?

A spark is a stream of electrons jumping across an air gap, heating the air until it glows and expands. Certain conditions can cause enough static electricity buildup to cause a spark or lightning. A spark often requires both a conductor and non-conductor. Lightning is an extreme example of a spark.

To understand what a spark is and how it is formed please read pg 309 - 310


Please read the text on pg 313 - 315. This will help describe how lightning is formed in case you missed today's class notes.
Make a copy of the diagram of how lightning is formed in your notes.


HOMEWORK:
Make sure that you answer the 6 questions that were on the blackboard!!

And incase you want a little light ( hahah get it light , spark, ya lame I know!) reading use this web site. http://www.findarticles.com/p/articles/mi_m1590/is_4_58/ai_79967168

Here is a brief and funny little clip on how lightning is created.
http://ksnn.larc.nasa.gov/videos_cap.cfm?unit=lightning



Click on here to see what the CIRCLE OF DEATH experiment looks like which we preformed in class. It was a shocking experience!http://cosmology.berkeley.edu/~swlh/tesla/sparks.jpg


Through the CIRCLE of DEATH we can experience, in a controlled way, how lightning works through familiar activities that generate a mild electrical spark or static. The principles behind the controlled experiences and actual lightning are basically the same. A closer look at lightning reveals that inside large cumulonimbus thunderclouds, violent air currents force water droplets and ice crystals to gain different charges and fill the cloud with static electricity. Positive charges collect at the top of the cloud, while the bottom becomes negatively charged. These charges become so intense that electricity is released with an enormous bolt, either within the cloud or to the ground. Lightning, then, is a huge discharge of static electricity that fills the gap between positive and negative charges.

http://bhs.broo.k12.wv.us/homepage/chip/current/rmaxwell/sparks.jpg