Atomic Bombs and How They Work

Atomic Bombs and How They Work There are two types of atomic explosions that can be facilitated by Uranium-235: fission and fusion. Fission, simply put, is a nuclear reaction in which an atomic nucleus splits into fragments (usually two fragments of comparable mass) all the while emitting 100 million to several hundred million volts of energy. This energy is expelled explosively and violently in the atomic bomb. A fusion reaction, on the other hand, is usually started with a fission reaction. But unlike the fission (atomic) bomb, the fusion (hydrogen) bomb derives its power from the fusing of nuclei of various hydrogen isotopes into helium nuclei. Atomic Bombs This article discusses the A-bomb or atomic bomb. The massive power behind the reaction in an atomic bomb arises from the forces that hold the atom together. These forces are akin to, but not quite the same as, magnetism. About Atoms Atoms are comprised of various numbers and combinations of the three sub-atomic particles: protons, neutrons, and electrons. Protons and neutrons cluster together to form the nucleus (central mass) of the atom while the electrons orbit the nucleus, much like planets around a sun. It is the balance and arrangement of these particles that determine the stability of the atom. Splitability Most elements have very stable atoms which are impossible to split except by bombardment in particle accelerators. For all practical purposes, the only natural element whose atoms can be split easily is uranium, a heavy metal with the largest atom of all natural elements and an unusually high neutron-to-proton ratio. This higher ratio does not enhance its splitability, but it does have an important bearing on its ability to facilitate an explosion, making uranium-235 an exceptional candidate for nuclear fission. Uranium Isotopes There are two naturally-occurring isotopes of uranium. Natural uranium consists mostly of isotope U-238, with 92 protons and 146 neutrons (92146238) contained in each atom. Mixed with this is a 0.6% accumulation of U-235, with only 143 neutrons per atom. The atoms of this lighter isotope can be split, thus it is fissionable and useful in making atomic bombs. Neutron-heavy U-238 has a role to play in the atomic bomb as well since its neutron-heavy atoms can deflect stray neutrons, preventing an accidental chain reaction in a uranium bomb and keeping neutrons contained in a plutonium bomb. U-238 can also be saturated to produce plutonium (Pu-239), a man-made radioactive element also used in atomic bombs. Both isotopes of uranium are naturally radioactive; their bulky atoms disintegrating over time. Given enough time (hundreds of thousands of years), uranium will eventually lose so many particles that it will turn into lead. This process of decay can be greatly accelerated in what is known as a chain reaction. Instead of disintegrating naturally and slowly, the atoms are forcibly split by bombardment with neutrons. Chain Reactions A blow from a single neutron is enough to split the less-stable U-235 atom, creating atoms of smaller elements (often barium and krypton) and releasing heat and gamma radiation (the most powerful and lethal form of radioactivity). This chain reaction occurs when spare neutrons from this atom fly out with sufficient force to split other U-235 atoms that they come in contact with. In theory, it is necessary to split only one U-235 atom, which will release neutrons that will split other atoms, which will release neutrons ... and so on. This progression is not arithmetic; it is geometric and takes place within a millionth of a second. The minimum amount to start a chain reaction as described above is known as supercritical mass. For pure U-235, it is 110 pounds (50 kilograms). No uranium is ever quite pure, however, so in reality more will be needed, such as U-235, U-238, and Plutonium. About Plutonium Uranium is not the only material used for making atomic bombs. Another material is the Pu-239 isotope of the man-made element plutonium. Plutonium is only found naturally in minute traces, so useable amounts must be produced from uranium. In a nuclear reactor, uraniums heavier U-238 isotope can be forced to acquire extra particles, eventually becoming plutonium. Plutonium will not start a fast chain reaction by itself, but this problem is overcome by having a neutron source or highly radioactive material that gives off neutrons faster than the plutonium itself. In certain types of bombs, a mixture of the elements Beryllium and Polonium is used to bring about this reaction. Only a small piece is needed (supercritical mass is about 32 pounds, though as little as 22 can be used). The material is not fissionable in and of itself but merely acts as a catalyst to the greater reaction.

Job Search Strategy Get 3 Offers

Job Search Strategy Get 3 Offers After doing a radio interview for WPR, I received an email from a listener containing some great job search advice. Her message reminded me of the success story I shared last week from one of my clients who was homing in on three job offers at once; this week’s story is from someone who set that as her goal. Together with the Job Search Success Survey Results from two weeks ago, they make a complete package! Here’s what Mary Beth, WPR listener, has to say (can you spot the empowering self-talk and empowering actions throughout?): Mary Beths Story One trick I used early in my career to motivate myself was to adopt the goal of getting three  attractive job offers at once.  This may sound preposterous or ludicrous, but here is why I found it worked for me and others with whom I shared the idea: The job hunt becomes a game Instead of feeling desperate like Oh man, I really need a job it was more like Can I possibly do this?   It seems challenging, but I wont know if I dont try.  Lets just see!   It is more motivating to try to get three attractive job offers than to shoot for just one. It offers a position of strength at a time when you might feel vulnerable.  Even when you are unemployed,  you will feel much less dependent upon any one job opportunity if you are trying to find three attractive opportunities.  This stretch goal encourages you to keep building momentum even when you have one or two good prospects, because you really dont know if they will pan out.  You wont allow yourself to coast with a few good leads if you are pushing for three attractive offers. It allows you to objectively know your worth. If you can bring multiple job offers to life at the same time, you are in a much better bargaining position.   Maybe one employer offers less money, but benefits you really value (flexible hours, more vacation time, an office vs. a cubicle). You can always use the terms of one offer to ask a prospective employer to enhance either the benefits package or the salary offering.  Sometimes employers dont have flexibility, but often they do. It leads to bigger salary increases. Early in my career, I was able to increase my salary $20-25,000 from one job to another using this strategy.  This was much better than 3-5% annual raises one usually receives while waiting for managers to decide to promote you. Is looking for three job offers more work than looking for a single job?  Probably.  Is it more fun?  Absolutely. To be honest, I never was able to bring three offers to life simultaneously, but frequently I was capable of bringing two to life at the same time.  Sometimes the third opportunity turned into a viable offer down the road. I learned to target my resume for the next step up and truly LOVE the job search. MORE Empowering Self-Talk Did you hear that folks? It is possible to LOVE the job search process! If you don’t, it might help to try Mary Beth’s strategy of seeking three offers instead of one. This strategy was underlying the success story last week as well. Or, engage in more of the empowering self-talk and empowering actions outlined in the Job Search Success Survey Results. There are limitless resources available to you – both your own internal resources and supportive external ones. Are you making the most of both of them? If you are, keep it up! And if not, consider that it might be time to start. Category:Job SearchBy Brenda BernsteinApril 30, 2013