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Published byBernard Gibson Modified over 8 years ago
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Do you know? He was born on January 17, in Boston in Masachusetts, and was the tenth child and youngest son of the family. His father was a candle maker. When he was young, he was not very good at math. He was curious and loved to learn about new things but he had only less than three years of formal education. He invented lightning rod.( 避雷针 ) He helped set up America’s first city hospital. He also helped to found a new nation. He helped to write the Declaration of Independence. He was a successful businessman, an inventor, a writer, a scientist and a world-famous statesman.
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Getting to know Benjamin Franklin Scientist/Inventor His famous kite experiment Eye glasses ◊, the lightning rod ◊, ◊ the odometer ◊, the Franklin stove ◊ ◊ Statesman( 政治家 ) Writer of “Declaration ( 宣言) of Independence” and “ Constitution (宪法) ” Ambassador ( 大使) to France Writer/Philosopher (Great thinker) Many famous wise sayings
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Quotations from Franklin But do you love Life, then do not squander Time, for that’s the stuff life is made of.
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Quotations from Franklin A lie stands on one leg, the truth on two.
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Quotations from Franklin Well done is better than well said.
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What does this experiment prove? The experiment proves that lightning and electricity are the same.
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Second reading: Scanning True/False statements Franklin’s famous kite experiment was conducted in the middle 1800’s. Franklin did the experiment to learn if kites can be used to attract lightning. When he saw some hairs on the string stand up, he knew that his experiment would work. He felt more than one electric shock during the experiment. F F T T
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True/False statements You need a kite, a key, some bad weather and a condenser in order to store electricity. You need a tail and a long string tied to the cross if you want to control the kite. Both the sticks of the cross are of the same length. The kite should be flown just before the rain comes. Dry strings conduct electricity very well. F F F T T
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Divide the whole text into three parts with the main idea given: Lead-in Sentences Describing the experiment Equipment needed Steps of the experiment Para 1 Para 2-3 Para 4 Para 5-6
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Franklin ’ s famous kite experiment Time: People: weather purpose The things needed The steps: June 1752 Franklin and his son Thunderstorm, rainy day To prove lightning and electricity are the same A kite, a key, some bad weather, a condenser First …… Second …… Third ……
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Complete the experiment report Hypothesis (假设) Tools and conditions Experiment steps Result Conclusion Whether lightning and electricity are the same? A kite, a key, a condenser, bad weather (storm). █ The string gets charged. Electricity is collected and stored. Lightning and electricity are the same.
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Qualities needed to be a scientist To be a scientist, we must be careful. be determined. work hard. be creative. have a clear conscience. be brave, or have courage.
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What’s wrong in this picture? Why?
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Franklin’s Famous Kite Experiment In the eighteenth century, Benjamin Franklin conducted a number of experiments in which he showed what electricity is. Here is how he described one of his experiments. In June 1752, I wanted to show that lightning and electricity are the same. Having realized that I could use a kite to attract lightning, I decided to do an experiment. I built a strong kite and waited for bad weather. When the first thunderstorm came, I took my condenser to a shed in the fields where I could do my experiment. My son helped me fly the kite.
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The kite flew high in the rainy sky, but nothing happened. I was beginning to think that the experiment would not work. Just then, I saw some of the hairs on the string stand up. The string was getting charged! I brought my finger close to the key and felt a light but very clear electric shock. Others followed even before the whole string was wet, and I was able to collect and store a great deal of electricity in the condenser. This experiment proves that lightning and electricity are the same.
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To do the experiment you need four things: a kite, a key, some really bad weather and a condenser, to store electricity. Most kites are made of paper, but a kite made of silk will not tear so soon in weather with rain and strong winds. Build the frame of the kite by making a small cross of two pieces of light wood. The pieces should be just long enough to reach the corners of the handkerchief. Tie the corners of the handkerchief to the points of the cross, and you will have a nice strong kite. Add a tail to the frame and tie a long string to the cross so you can control the kite.
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The next three steps are very important. First, fix a very sharp piece of metal, pointing a foot or more above the frame, to the top of the longer stick of the cross. Second, fasten a key to the end of the long string. Third, tie a silk ribbon to the string, just above the key. This ribbon, which must not get wet, will protect you from the electricity.
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Fly the kite when a thunderstorm appears to be coming on. Stand inside a door, or under some cover, so that the silk ribbon does not get wet. Take care that the string does not touch the wall or the door. When a thundercloud comes over the kite, the sharp piece of metal will pull the electricity from the cloud. The kite and the string will become charged. When the kite and the string are wet from the rain, they will conduct the electricity very well. You can collect and store the electricity in the condenser and use it for other experiments.
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Experiment steps 1. Make a kite with a silk handkerchief; 2. Fix a sharp piece of metal on the kite; 3. Fasten a key to the end of the long string; 4. Fly the kite when a storm is coming on; 5. Collect and store the electricity in the condenser.
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