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SŪTRA I (Pudgala)
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embedded in these rocks together with uranium in a fixed proportion. It is in fact with the help of the uranium-lead ratio that the age of these rocks is estimated, thus establishing beyond doubt that lead is formed by the gradual disintegration of uranium.
We shall now give an account of the work which has been done in the Cavendish Laboratory of England in order to produce one kind of atom from another kind artificially.
Figure 5 shows the nucleus (central core) of an atom of nitrogen gas and at the right-hand top corner of the same is shown an alpha particle which has been used as a bullet in the experiment.
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ALPHA PARTICLE BULLET
Nucleus of Nitrogen atom before bombardment. The bigger circle represents the central core (nucieus) of the nitrogen atom. It consists of three alpha particles, one proton and one neutron. The three alpha particles are shown by three smaller circles within the big circle. The symbol (+) represents a proton and the black disc, a neutron. Each alpha particle again consists of two protons and two neutrons.
Fig. 5
The above figure shows that an alpha particle bullet from an outside source is just on the point of being short into the
