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That is what I thought was happening in the experiment , please correct my interpretation.
Quote from: Thebox on 13/08/2017 22:29:56That is what I thought was happening in the experiment , please correct my interpretation.Read all about it.https://en.wikipedia.org/wiki/Cloud_chamber
I have some key things for you to read ''But it turns out that Nature has been kind enough to present us with just such objects, so that by comparing the observed mass of the charged one with the observed mass of the neutral one, we can tell whether there is any electromagnetic mass. For example, there are the neutrons and protons. They interact with tremendous forces—the nuclear forces—whose origin is unknown. However, as we have already described, the nuclear forces have one remarkable property. So far as they are concerned, the neutron and proton are exactly the same. The nuclear forces between neutron and neutron, neutron and proton, and proton and proton are all identical as far as we can tell. Only the little electromagnetic forces are different; electrically the proton and neutron are as different as night and day. This is just what we wanted. There are two particles, identical from the point of view of the strong interactions, but different electrically. And they have a small difference in mass. The mass difference between the proton and the neutron—expressed as the difference in the rest-energy mc2mc2 in units of MeV—is about 1.31.3 MeV, which is about 2.62.6 times the electron mass. The classical theory would then predict a radius of about 1313 to 1212 the classical electron radius, or about 10−1310−13 cm. Of course, one should really use the quantum theory, but by some strange accident, all the constants—2π2π’s and ℏℏ’s, etc.—come out so that the quantum theory gives roughly the same radius as the classical theory. The only trouble is that the sign is wrong! The neutron is heavier than the proton.Nature has also given us several other pairs—or triplets—of particles which appear to be exactly the same except for their electrical charge. They interact with protons and neutrons, through the so-called “strong” interactions of the nuclear forces. In such interactions, the particles of a given kind—say the ππ-mesons—behave in every way like one object except for their electrical charge. In Table 28–1 we give a list of such particles, together with their measured masses. The charged ππ-mesons—positive or negative—have a mass of 139.6139.6 MeV, but the neutral ππ-meson is 4.64.6 MeV lighter. We believe that this mass difference is electromagnetic; it would correspond to a particle radius of 33 to 4×10−144×10−14 cm. You will see from the table that the mass differences of the other particles are usually of the same general size.''http://www.feynmanlectures.caltech.edu/II_28.htmland further...''You are no doubt worried about the different signs of the mass differences in the table. It is easy to see why the charged ones should be heavier than the neutral ones. But what about those pairs like the proton and the neutron, where the measured mass comes out the other way? Well, it turns out that these particles are complicated, and the computation of the electromagnetic mass must be more elaborate for them. For instance, although the neutron has no net charge, it does have a charge distribution inside it—it is only the net charge that is zero. In fact, we believe that the neutron looks—at least sometimes—like a proton with a negative ππ-meson in a “cloud” around it, as shown in Fig. 28–5. Although the neutron is “neutral,” because its total charge is zero, there are still electromagnetic energies (for example, it has a magnetic moment), so it’s not easy to tell the sign of the electromagnetic mass difference without a detailed theory of the internal structure.''