Electrical Properties

Question 1

One of the most important electrical characteristics of a solid
material is the ease with which it transmits an electric current. It relates the current I—or time rate of charge passage— to the applied voltage V

Answer 1

OHM’S LAW

Question 2

The value of R is influenced by specimen configuration, and for many materials is independent of current. It is independent of specimen geometry but related to R

Answer 2

Electrical resistivity ρ is

Question 3

is used to specify the
electrical character of a material. It is simply the reciprocal of
the resistivity

Answer 3

Electrical conductivity σ

Question 4

results from the motion of electrically charged particles in response to forces that act on them from an externally applied electric field. Positively charged particles
are accelerated in the field direction, negatively charged particles in the direction opposite.

Answer 4

Electric current

Question 5

Within most solid materials a current arises from the flow of
electrons, which is termed electronic conduction. In addition,
for ionic materials a net motion of charged ions is possible that
produces a current;

Answer 5

Ionic conduction

Question 6

2 Band structure

Answer 6

Valence Band
Conduction Band

Question 7

filled-highest occupied energy levels

Answer 7

Valence Band

Question 8

empty-lowest unoccupied energy levels

Answer 8

Conduction Band

Question 9

Four possible electron band structures for solid materials.

Answer 9

*electron band structure found in metals (copper) which electrons states above and adjacent to filled states, in the same band
*electron band structure of metals (magnesium), there is overlap of filled and empty outer bands
*electron band structure of insulators; filled valence band is separated from the empty conduction band by large band gap
*electron band structure in semi conductors, which same as for insulators except that the band gap is narrow.