Tuesday Dec. 9, 2008
The music today was Stairway to Heaven
from Led Zeppelin. It's one of my favorite songs and I've been
wanting to play it in ILC 140 for some time.
A quick review of my weekend
Course evaluation
Quizzes and grade summaries will be returned at this point.
Please check them carefully for errors.
A few remaining notes on Lightning Safety (see below)
Some information about the Final Exam and the Reviews planned prior to
the exam. You'll find everything you need to know on the Final Exam Study Outline. Note the
reviewing will start on Wednesday in the MWF section. You are
welcome to attend (they meet from 2-2:50 in BioWest 301). You are
welcome also to take the Final Exam with the MWF section this coming
Friday (Dec. 12) from 2-4 pm in BioWest 301. You must let me know
ahead of time, however.
7 Questions on the Final Exam will be taken from the NATS 101 Finale handout that
was covered at the end of class today.
Lightning
is a serious weather hazard and kills just under 100
people every year in the United States. We discussed some
lightning safety rules that you should keep in mind during
thundery weather.
Stay away from
tall isolated objects
during
a lightning
storm.
You can be hurt or killed just by being close to a lightning strike
even if you're
not struck directly.
An automobile with a metal roof and body provides good
protection from
lightning. The lightning current will travel through the metal
and around the passengers inside. The rubber tires really don't
play any role at all. The people in Florida that were
triggering lightning were inside a metal trailer and were perfectly
safe. All of the connections made to equipment outside the
trailer was done using fiber optics, there were no metal wires entering
or leaving the trailer.
You shouldn't use a corded phone and electrical
appliances
during a lightning storm because lightning currents can follow wires
into your home. Cordless phones and cell phones are safe.
It is also a good idea to stay away from plumbing as much as possible
(don't take a shower during a lightning storm, for example). Vent
pipes that are connected to the plumbing go up to the roof of the
house, an ideal location to be struck.
To
estimate the distance to a lightning strike
count the
number of
seconds between the flash of light and when you first hear the
thunder. Divide this by 5 to get the distance in miles.
The
latest lightning safety recommendation is the 30/30 Rule.
The 30/30 rule
People should seek shelter if the delay in seconds between
a lightning flash and its
thunder is 30 seconds or less.
People should remain under cover until
30 minutes after the final clap of thunder.
