________________
of minimum energy, such a material acquires a state of
minimum energy on crystallisation. (c) GTA 467ef (EITE) À CE , À HHÀ So faig ui ont - Kakani,
Saxena, Chhajer & Lodha, Electricity and Electronics, p. 2 “'Electron Emission "'The emission of electric charges from hot bodies constitutes thermionic emission. Edison discovered that current travels from a negative potential to positive potential through a vacuum. Structure of Solids : According to present concepts a metal is regarded as a conglomerate of crystals. Within each crystal the atoms are held by interatomic forces in a regular pattern of space lattice. Each atom in turn consists of a nucleus surrounded by moving electrons travelling in well-defined orbits. Some of the electrons in the outer orbit of an atom are not rigidly bound to the atom, but are relatively free to travel more or less independently from one atom to the another. These are known as free electrons and it is these free electrons which are responsible for most of the electrical and in this chapter, we will study the effects associated with motion of
electric charges. Moving charges constitute the electric currents. 39. (a) Gujarat state Board of School Textbooks' Textbook of Physics (Part
- I) (Std. XII), pp 169-17 (Chapter 7 on Electrical Corrents) ''In this chapter we will study the effects associated with motion of electric charges. Moving charges constitution the electric currents.
To the Positive Tennial of Battery
To the Negative Terminal of Battery
Direction of the field in the conductor
"Suppose a conductor is connected to the terminals of a battery as shown in fig. To understand the process occurring in the conductor microscopically, we should first understand the internal structure of a metalic conductor. In a metalic substance, the valence electrons of the constituent atoms do not remain attached to their respective parent atoms, but get detached, leaving the atoms as
THAT Y511 37361 - Harola, 2003
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