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Mary and Christian


 * //Hi Mary.My name is Christian Bell and I am from Bankhead,Georgia.I just moved here about 6 months ago.Before I moved to Bankhead,Georgia,I lived in Destin,Florida.It was very warm there also.But I have to admit that I really loved It down there.The beaches,shopping malls,water parks.!! Everything was so exciting.It was beautiful.But I had to move to Georgia because I was offered a job here in Bankhead.I dont like Georgia as much as I love Florida.Georgia is cool to.We have all sorts of things to do here.So it's pretty ecxiting here also.What about you??//**

Christian!!!


 * My name is Mary Wilson and I'm from Europe :]. I move alot around Europe, my job requires me to do that. I am currently in Paris right now. Paris is a great place, all the sights are AMAZING!! I love to travel, so I have been all around the world. That is one good thing about having a job that requires to move is that you can see so much of the world! So I see that you live in the USA. I have a few family members that live there. Never been to Georgia though. Been to FLorida and Alabama though! The good ol south lol. So tell me a little about youself?? :)**

**** J. J. Thomson considered that the structure of an atom is something like a raisin bread, so that his atomic model is sometimes called the **raisin bread model**. He assumed that the basic body of an atom is a spherical object containing //N// electrons confined in homogeneous jellylike but relatively massive positive charge distribution whose total charge cancels that of the //N// electrons. The schematic drawing of this model is shown in the following **figure**. Thomson's model is sometimes dubbed a **plum pudding model**.
 * I have found some research on our model. They call the Thomson model "raisin bread" b/c it is round w/ little circles in it. It's also called the "Plum Pudding Model". They have some odd names for models. J.J. Thomson discovered electrons(negative) in 1897. All the positive balances the negative out. It says that the negatives are the "plum" and they are floating around in "pudding". Well if you find any more information about Thomson's model, let me know!!**
 * || [[image:http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/1x1.gif]] [[image:http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/P24_E/Thomson_model_E.jpg]] [[image:http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/1x1.gif]] ||

Hi Mary!! It's me again. I found some more information on the J J Thompson model. **__CHECK IT OUT!!!__** As stated on the preceding page, Geiger and Marsden carried out an experiment in which the alpha rays were collided against a thin metal foil. Their results showed that almost all incident alpha particles penetrate the foil and go straight in forward direction but **a few are scattered in very large angles**. Is it possible to explain this result by using Thomson's model? This question will be studied below, but before explaining it, let us present the answer in advance: **The results of the alpha particle scattering cannot be explained by Thomson's atomic model**. Thomson's raisin bread model (plum pudding model) therefore cannot be valid as an atomic model. The reason will be explained below. Since we need somewhat detailed mathematical expressions, it will be given on the other page,  As seen on the other page (2-4-A), we can consider that the scattering angle of the alpha particle by Thomson's model is at most **0.01 degrees**. The thickness of the metal foil in the scattering experiment of the alpha rays is about 10-6 m. When assuming that the atoms are tightly packed in the metal, there are about 10000 atoms lining up in the direction of thickness, because the size of an atom is approximately 10-10m. (See the following **figure**.)
 * __YOU CAN FOLLOW THIS SITE TO GET MORE INFORMATION ON HIS MODEL!!__** So.......is it fun traveling all around the world?? I bet you that it is so amazing. Are you married?? Do you have any kinds??
 * || [[image:http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/1x1.gif]]**[Thomson's Model [[image:http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/1x1.gif]]and Alpha Particle Scattering]** [[image:http://www2.kutl.kyushu-u.ac.jp/seminar/MicroWorld1_E/Part2_E/1x1.gif]]



When the alpha particle collides with these atoms in the metal foil 10000 times successively, the scattering angle of each individual collision in such a **multiple scattering** is less than **0.01 degrees** as discussed above. The resultant scattering angle is obtained by an accumulation of these individual scatterings of 10000 times. One may expect that, even if the scattering angle of each individual scattering is very small like 0.01 degrees, we can have as large resultant angle as This is however unrealistic, because the direction of each individual scattering must be **random**, and an accumulation of random values would give nearly zero only. So that we never obtain such a large resultant scattering angle after the multiple scattering. Accordingly, such a large scattering angle as those obtained in Geiger and Marsden's experiment cannot be reproduced by such a multiple scattering as stated above. Thus we can conclude that **Thomson's atomic model is not held**. ||

Your assigned Atomic Model is: Thomson