Inside C12 Name: Marvin S. Status: N/A Age: 40s Location: N/A Country: N/A Date: Sunday, September 15, 2002 Question: If I were to go inside a c-12 atom and my size was thousands of times smaller than an electron, what would I see? Replies: Marvin, At the center of the atom is a small but heavy cloud, the nucleus. This cloud has twelve extremely heavy particles with practically no size to them. They are moving too fast to actually see, shooting around within this cloud. Six are very electrically active, always absorbing and releasing little bundles of electrical energy called photons (light at the scale of particles). These six electrically active particles are protons. Also shooting around within the nucleus are the six less active particles called neutrons. All twelve of these particles are constantly shooting particles called pions back and forth between each other. There is much more within the nucleus than just six protons and six neutrons. Outside the center is a cloud of electrons. If the nucleus seems to be about a foot wide, the electron cloud is about two miles wide. Usually there are twelve electrons shooting every which way too fast to even try to see. You just see a "cloud of motion". Like protons, these electrons are very active, always absorbing and emitting photons. An electron that absorbs energy from a photon speeds up and jumps toward the outside of the cloud. An electron that loses energy to a photon drops inward from the outside of the cloud. Whether you are inside the nucleus or in the electron cloud, you had better hope nothing hits you. Dr. Ken Mellendorf Physics Instructor Illinois Central College An interesting question, but the answer is "nothing". In fact, the question is not well defined in a number of ways; our life depends on atoms being MUCH smaller than we are. Are you assuming your eyes would be made of the same molecules, except smaller? That is, however, not possible since Planck's constant really defines what we mean by "small"; you cannot have smaller molecules. Also, you need photons to see. The photons that your eyes are sensitive to correspond to wavelengths MUCH longer than the sizes of molecules and so cannot be used to "see" any detail in molecules. For example, the smallest orbit of a hydrogen atom has a radius of 0.053 nm (1 nm = 10-9 m = 0.000000009 m) and visible light has a wavelngth around 500 nm. Photons with wavelengths small enough to "see" an atom would be so energetic that they would break up an atom since their energy is inversely proportional to their wavelength. For many reasons, life of complexity similar to us must remain at about our size, certainly large enough that atoms are MUCH smaller. Another problem with your question is that an electron, as far as we know, is a point particle. That is, it is of zero size and so neither you nor anything else can be smaller than an electron. It is indeed a strange universe out there! The strangest part may be that it is put together in a way that makes our life possible. Best, Dick Plano Click here to return to the Physics Archives

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