supposed to be distributed uniformly over a sphere of radius a, for speeds slow compared with the velocity of light, the apparent mass
Therefore
Taking the value of e as 1·13 × 10-20, a is 1·4 × 10-13 cms.
Thus the diameter of an electron is minute compared with the diameter of an atom.
83. Distribution of velocity amongst the β particles. Some interesting experiments have been recently made by Paschen22 to determine the relative number of β particles which are expelled from radium at the different speeds. The experimental arrangement is shown in Fig. 29.
A small thin