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Electrons; Ionization

المؤلف:  GEORGE A. HOADLEY

المصدر:  ESSENTIALS OF PHYSICS

الجزء والصفحة:  p-517

2025-12-30

578

When a charged gold-leaf electroscope is surrounded with air in normal condition, it will retain its charge. As soon, however, as X-rays or the radiations from radium fall upon it, it loses its charge and the leaves fall together. To explain this change in the conductivity of the air it is necessary to consider the modern theory of the atom. This is that the atom is a complex structure consisting of minute negatively charged particles in rapid motion, connected with positively charged particles which are themselves in motion. The negatively charged particles are called electrons. The velocity with which the a-rays and B-rays leave a radio-active material is probably due to the velocity which the charged particles have within the atom, and which they retain as they leave it. It is supposed that the X-ray pulses separate electrons from the atoms in air. This leaves the air a mixture of negatively charged electrons and positively charged particles, thus making it a conductor, or ionizing it.