ROOTS of ELECTRICITY

An Elementary Particle

Ad far back as 440 B.C., the atom was was thought of being the “indivisible and indestructible component of an element.” Correcting this notion has prompted the definition of elementary particles, such as electrons, protons, photons, and neutrons.

In essence, an elementary particle is one that cannot be reduced further without losing its physics characteristics. We will focus our initial discussion on one such particle, the electron. The electron is one of the most important of the fundamental, stable and elementary subatomic particles of matter.

The Electronic Charge, e

The most popular model of the atom, as proposed by Ernest Rutherford with supported by the evidence generated in the Geiger-Marsden Gold Foil experiment, is that of a planetary model. The nucleus of the atom, which is dense in mass and positively charged, is surrounded by fast moving negatively charged electrons. Neil Bohr’s work on the atomic model and Max Planck’s contributions have both been phenomenal in the field of Quantum Theory. 

Here are some facts about the electron:

• 1. The symbol for electronic charge is e.
• 2. The magnitude of the unit of charge on an electron is 1.60x10^–19 C, to 3 sig. figs. 
• 3. The mass of the electron is 9.11x10^–19 kg, which is ~1/1836 times the mass of a proton.
• 4. For many year, scientists only used the charge to mass (e/m) ratio of ions in many scientific calculations. The value of e was unknown.
• 5. Robert Millikan’s work, the famous Oil Drop experiment, was an innovative design used in arriving at 2 very important conclusions related to the nature of electronic charge! (HW.01).
• 6. The electron exhibits both ‘wave-like’ and ‘particle-like’ behaviors, supporting the Duality Theory of Matter.