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Build An Atom

Michio Kaku once said that He build an atom smasher in his garage as a science fair project in high school. He said he used 400 pounds of transformer steel and 22 miles of copper wire. But I would like to know how he did it exactly? Can you give me more details about it ?

Build An Atom

I think Kaku is slightly tongue in cheek / self disparaging when he calls it an atom smasher, and this, allied with the complaining neighbors, makes me doubt if he got the chance to run it very often to smash atoms.

I do imagine he is exaggerating this claim however on the same note I have built a betatron from a plain incandescent light bulb using the driver from a plasma globe and two speaker magnets. That is a cakewalk. I also attempted to build a ten thousand volt transformer as a driver to a tesla coil. That failed as I had not enough iron for the magnetic flux. I caused a brown out every time I ran it. It did produce enough voltage to break two inches of air though. That kind of set up though is expensive. About the miles of copper. Yeah I can relate took me eight hours to wind one by hand for the secondary for my tesla coil I used 38 guage about as fine a thread as my hair for perspective.

However, BECs are something of a paradox. They are very fragile and are rapidly destroyed when light falls on them. Yet the presence of light is crucial in forming the condensate: to cool a substance down to a millionth of a degree; one needs to cool down its atoms using laser light. As a result, BECs were restricted to fleeting bursts, with no way to sustain them coherently.

This lesson provides students with the basic foundations of atomic theory and a simple understanding of the periodic table. It provides an easy-to-understand Prezi presentation before leading students into an easy and fun atom building simulation. Assessments are scored by the progam. A vocabulary website is also provided. It can be used on iPads or in a computer lab.

How close were the Nazis to developing an atomic bomb? The truth is that National Socialist Germany could not possibly have built a weapon like the atomic bombs dropped on Hiroshima or Nagasaki. This was not because the country lacked the scientists, resources, or will, but rather because its leaders did not really try.

They were certainly trying to win the war. And they were willing to devote huge amounts of resources to building rockets, jet planes, and other forms of deadly and sometimes exotic forms of military technology. So why not the atomic bomb? Nazi Germany, it turns out, made other choices and simply ran out of time.

Researchers knew that they could manufacture significant amounts of uranium 235 only by means of isotope separation. At first German scientists led by the physical chemist Paul Harteck tried thermal diffusion in a separation column. In this process, a liquid compound rises as it heats, falls as it cools, and tends to separate into its lighter and heavier components as it cycles around the column. But by 1941 they gave up on this method and started building centrifuges. These devices use centripetal force to accumulate the heavier isotopes on the outside of the tube, where they can be separated out. Although the war hampered their work, by the fall of the Third Reich in 1945 they had achieved a significant enrichment in small samples of uranium. Not enough for an atomic bomb, but uranium 235 enrichment nonetheless.

At best this would have been far less destructive than the atomic bombs dropped on Japan. Rather it is an example of scientists trying to make any sort of weapon they could in order to help stave off defeat. No one knows the exact form of the device tested. But apparently the German scientists had designed it to use chemical high explosives configured in a hollow shell in order to provoke both nuclear fission and nuclear fusion reactions. It is not clear whether this test generated nuclear reactions, but it does appear as if this is what the scientists had intended to occur.

All of this begs the question, why did they not get further? Why did they not beat the Americans in the race for atomic bombs? The short answer is that whereas the Americans tried to create atomic bombs, and succeeded, the Germans did not succeed, but also did not really try.

This can best be explained by focusing on the winter of 1941-1942. From the start of the war until the late fall of 1941, the German "lightning war" had marched from one victory to another, subjugating most of Europe. During this period, the Germans needed no wonder weapons. After the Soviet counterattack, Pearl Harbor, and the German declaration of war against the United States, the war had become one of attrition. For the first time, German Army Ordnance asked its scientists when it could expect nuclear weapons. The German scientists were cautious: while it was clear that they could build atomic bombs in principle, they would require a great deal of resources to do so and could not realize such weapons any time soon.

Army Ordnance came to the reasonable conclusion that the uranium work was important enough to continue at the laboratory scale, but that a massive shift to the industrial scale, something required in any serious attempt to build an atomic bomb, would not be done. This contrasts with the commitment the German leadership made throughout the war to the effort to build a rocket. They sunk enormous resources into this project, indeed, on the scale of what the Americans invested in the Manhattan Project.

Thus Heisenberg and his colleagues did not slow down or divert their research; they did not resist Hitler by denying him nuclear weapons. With the exception of the scientists working on Diebner's nuclear device, however, they also clearly did not push as hard as they could have to make atomic bombs. They were neither heroes nor villains, just scientists working on weapons of mass destruction for Hitler's Germany.

An A-bomb ( or atomic bomb) is generally considered to be one based on the fission principal - that is the splitting of atoms. An H-bomb (or hydrogen bomb) is based on the principal of fusion, that is the fusing of atoms together. H-bombs are generally much more powerful than A-bombs. The largest A-bomb tops out at the equivalent of 0.7 megatons of TNT, while the largest H-bomb ever produced was 50 megatons. The heat and pressures needed in order to get an H-bomb's fusion reaction going, however, can only be produced on earth at the heart of a fission bomb, so in effect every H-bomb has an A-bomb as a part of its mechanism. For more information on how to build a hydrogen bomb, see our page.

In 1945 an atomic bomb worker, Harry K. Daghlian Jr, was killed while experimenting with plutonium. The test was designed to see just how much of a neutron reflector was needed to push the sphere of plutonium to the edge of going supercritical with the experimenter gauging how close he was getting by listening to a Geiger counter. As he moved the final "brick" of reflective material close to the sphere he realized he should not place it in position, but then it slipped from his hand. Daghlian knocked the brick away, but it was too late. The sphere went supercritical with a flash of blue light. He was exposed to 510 REMs of radiation and after an agonizing illness, died 28 days later.

This lesson is the first to begin to truly address HS PS1-1: Using the periodic table as a model to predict properties of elements based on the patterns of electrons in the outermost energy level of atoms. This is the first NGSS Performance Expectation that asks students to use the periodic table, and this activity begins to introduce them to the format of individual cells of the periodic table, and how protons are related to atomic number and identity of elements.

Students will engage this after learning about the discoveries of the electron and the nucleus, but likely with an incomplete visual model of the atom. Our emphasis today is on Science and Engineering Practice 2, Using models. Our model of choice is a computer model provided by the PhET project at the University of Colorado Boulder. This is a free online simulation it that I use a lot throughout the year to provide clear visuals for students. It does require Java, so it may not be accessible in all locations. However, this particular simulation is also available via HTML5, and runs on tablets, netbooks and smartphone browsers.

We also will be tapping into Science and Engineering Practice 4, Analyzing and interpreting data, as students will decide which particles to add in each trial, and record what is changing to determine the properties of each subatomic particle. From their data, they will use Science and Engineering Practice 6 and construct an explanation from their simulation results -- both individually and together in small groups.

In the high school setting, it is easy for students to view each day, and each class, as a series of disconnected events. This bellringer is designed to connect what we have done thus far. We have been working with the terms atom, proton, neutron and electron as vocabulary terms, as well as studying the historical experiments which led to the discovery of these particles. Asking students to visually represent atoms provides both a formative assessment of where they are in their mental model of the atom, but it also gives the opportunity to ask probing questions to connect parts of their drawings to the experiments we have studied, building and connecting the prior knowledge from the previous class dates.

As students enter, the direction \"Draw an atom on a piece of paper\" is on the board. When the bell rings, I ask students to find a blank page in their binders and complete the activity while I take attendance.

I then tell the class today we will be using the computers to build upon and enhance our understanding of the atom's structure. I ask students to go back with their partners and log into the computers. Our system often takes up to three minutes to log in, so this provides a transitional time.

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