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					Unit 16 Reading

If you won’t be forgotten after death,
either write things worth reading, or
do things worth the writing.
           ------------- Benjamin Franklin
Warming up: Do you know ?

   Some scientists in the 18th & 19th centuries

   Physics        Medicine        Chemistry         Biology
                  Florence       Watson & Crick
Madame Curie                                      Charles Darwin
    radium (镭)      pie charts      DNA           evolution(进化)
radioactivity(放射) (圆形分格统计图表)
                                                  Carl Linnaeus
Isaac Newton     Louise Pasteur Mendeleyev
gravity (重力)     germs (细菌)     periodic table    naming plants
                                of elements
What can you think of
  Do you know about
      Franklin (1706-1790)
He was born on Jan. 17, in Boston Massachusetts.
He wasn’t very good at math when he was young.

He had only less than 3 years of school education.
He was curious and loved to learn about new things.

He invented the lightning-rod(避雷针).
He helped to found a new nation --- USA.
He helped write the Declaration of Independence(独立宣言).

He was an inventor, a writer, a scientist, a businessman
and a world-famous statesman(政治家).
 Skimming:   Listen, read, then decide            true or

   In 1752 scientists already knew what           T
electricity was.
  Franklin was helped by a friend to do the
    Franklin made the kite of silk because wet
silk does not conduct electricity.
   A condenser was used in the experiment          T
to store electricity.
  The key tied to the string was put into the
door to stop the kite flying away.                 F
Scanning:   Which ones are correct?
Qs:   Why did he do this experiment with a kite?
      Why did he make the kite of silk, not paper?

      Is this experiment dangerous? Why?
      What did this experiment prove?
This proved that lightning and electricity are the same.
 Read &
 discuss:    purpose: to prove lightning &
                       electricity are the same
             what\do: built a strong kite
             when\do: in bad weather
Franklin’s   what\    got charged, and
famous       happened: felt electric shock
kite          result: proved the idea
             things\ a kite, a key, some bad
             needed: weather, a condenser
                      1. fix a sharp piece of metal
                      2. fasten a key to the end of
             steps:      the long string
                      3. tie a silk ribbon to the string
Franklin’s kite experiment
 1.What did he do, after he had realized that
he could use a kite to attract lightning?

 Having realized that he could use a kite to
attract lightning, he decided to do an experiment.
 (After he had realized ------, he decided -------.)

What did you do, after you had found no buses?
Having found no buses, I decided to take a taxi.
2. What will you have, if you tie the corners of the
handkerchief to the points of the cross?

 Tie the corners of the handkerchief to the points
of the cross, and you will have a nice strong kite.

What will you say, if your friend will be late?
 Hurry up, and you will be on time.
 Hurry up, or you won’t be on time.
3.What is the use of the silk ribbon?

This ribbon will protect you from the electricity.
It will prevent the electricity from hurting you.

Why do you like to wear hats on summer days?
 A hat will protect us from the sun.
 A hat will prevent the sun from hurting us.
Things needed
to make a kite:


     a kite

How to make the kite?

Build…    Tie…to
Add…to    …
…           …
First, fix…
Third, tie…
Fourth, fly…
    In order to prove that ______ are the same,
Franklin built a strong _____. When the ____ came,
he did the ____ by using his ____ and condenser.
    He found the string was ____ and he could feel a
light but very clear ___. So he ___ a great deal of ___
in the condenser. This proved _____.
   To do the ___, ___ are needed:
a __, a __, some___ and a condenser.
   The next _____ are very important.
   1, fix a sharp piece of _____.
   2, fasten a ____ to the end of ___.
   3, tie a ____ to the long string.
Homework: writing
                    (Kite) Experiment Report

 Title              Experimenter’s name



Knowledge is power.

             -------- ( F. Bacon 培根)

Knowledge is a treasure, but practice is the key to it.

             -------- ( Fuller 富勒)

Genius is 1% inspiration and 99 % perspiration.

             ------- (T. Edison 爱迪生)

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