Electric
current passes through a filament of an incandescent bulb, thereby increasing
it temperature. When current flows, it contains electrons through the filament
to produce light. Typically, incandescent light bulb consists
of a glass enclosure that contains tungsten filament. The glass enclosure
contains either a vacuum or an inert gas that serves as the filament protection
from evaporating. Incandescent light bulbs contain a stem attached at to its
base to allow the electrical contacts to run through the envelope without gas
or air leaks.
