Lightning
If you missed today:
1. We watched a viper roller coaster video AND took a survey of how many students are going to 6 Flags Great America on May 3rd Physics Day (Let us know right away what you plan on doing, probably $60 for ticket and bus.
2. Around the classroom
had a student explain electrophorus on the side while doing it
had a student explain rolling pop can
had a student explain hovering plastic bag hoop with pvc
had a student explain electrophorus on the side while doing it
had a student explain rolling pop can
had a student explain hovering plastic bag hoop with pvc
3. Showed first lightning video which explains how lightning forms and shows a slow motion of a lightning strike.
4. Showed a 5 year map (1996-2000) of lightning strikes in the U.S.
5. A video showing a simulation of a car getting struck by lightning
6. What to do in a lightning storm
7. The Farmer ask a Lightning Expert why randomly only half his cows died in the pasture when it was hit by lightning
Smart Board Diagram of Electric Fields Potential Rings around a Lightning Strike
Which cow(s) died? If all four cows feet are in the same potential voltage ring, the cow lives. If feet are in different potential voltage differences then the cow dies. That is why you put your feet together and minimize the size of contact with the ground.
Which cow(s) died? If all four cows feet are in the same potential voltage ring, the cow lives. If feet are in different potential voltage differences then the cow dies. That is why you put your feet together and minimize the size of contact with the ground.
8. Two Ways a Lightning Rod is a defense against lightning:
a). The obvious reason is that a lightning rod has a copper wire running to a pipe or other metal rod pounded into the ground. So if lightning strikes the lightning rod the path of least resistance is to the ground by the way of the thick copper wire.
b). The less obvious reason is the a pointed object has a larger charge density around the point which attracts the neutral air molecules which picks up the charge then (now that the air molecule is the same charge) repels (extreme acceleration away) the lightning rod, neutralizing the object continuously. Note diagram below and that the electric field lines are closer near the pointed end.
b). The less obvious reason is the a pointed object has a larger charge density around the point which attracts the neutral air molecules which picks up the charge then (now that the air molecule is the same charge) repels (extreme acceleration away) the lightning rod, neutralizing the object continuously. Note diagram below and that the electric field lines are closer near the pointed end.
