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35. (a)
Proton breaking into Neutron + Positron, and Neutron breaking into Proton+Electron.” J.S. Zaveri and Muni Mahendra Kumar, Microcosmology :
Theory of Atom in Jain Philosophy and Modern Science, pp. · 38, 39.
“Characteristics of Subatomic Particles Fundamental th know about the subatomic particles is that every particle of the same species looks exactly alike. Every electron, proton and neutron looks exactly like every other electron, proton and neutron respectively. Mass : Particles of different types, however, can be recognized by their distinguishing characteristics. Mass is the first distinguishing characteristic. A proton has about 1980 times more mass, than an electron. (This does not mean that proton is 1800 times larger than electron. A kilogram of iron has the same mass as a kilogram of cotton). Mass of a particle at rest is called its rest-mass. The mass of a moving particle increases with its velocity and at 99% of the speed of light it is seven times larger than the rest-mass. At velocities above 99% of the speed of light, particle-masses increase dramatically. An electronvolt is a unit of energy but it is also used for measuring a particle's mass (the energy that an electron gains from an electric field of one volt is called an electron-volt). Thus the rest-mass of an electron is 0.51 million electron volts (Mev) while the rest-mass of a proton is 938.2 Mev. It is customary to use the mass of an electron as a unit. This arrangement makes the mass of a proton 1836.12 and the mass of a neutron 1837. By this system it is easy to see how much heavier a particle is than an electron. A photon has zero rest-mass, and is therefore, called massless particle. (“Massless", is actually a clumsy translation from the language of mathematics to English language.) All its energy is the energy of motion at the speed of light. It can neither be slowed down noi made to run faster. Electric Charge : The second characteristic of a subatomic particle is its charge. Every subatomic particle has either a positive charge or a negative charge or is neutral. Its charge determines how the particle will behave in the presence of other particle. A neutral particle will be utterly indifferent to all other
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