when electric Current flows thru fillament?
2006-09-11 02:39:15 · 4 answers · asked by goring 6 in Science & Mathematics ➔ Engineering
DC current flow?
2006-09-11 02:54:21 · update #1
is dc current flowS in one directiron and the electron should hit the first resistance which is the first end of the filament ,other wise curent flow positive to negative has nothing to do with electron directional motion?
2006-09-12 02:16:36 · update #2
The incandescent light bulb or incandescent lamp is a source of artificial light that works by incandescence. An electric current passes through a thin filament, heating it and causing it to emit light. The enclosing glass bulb prevents the oxygen in air from reaching the hot filament, which would be otherwise rapidly destroyed by oxidation.
Incandescent bulbs are also called electric lamps, extending the use of a term applied to the original arc lamps, and in Australia and South Africa they are also called light globes. A benefit of the incandescent bulb is that they can be produced for a wide range of voltages, from a few volts to several hundred volts. Because of their relatively poor luminous efficacy, incandescent light bulbs are gradually being replaced in many applications by fluorescent lights, high-intensity discharge lamps, LEDs, and other devices.
2006-09-11 02:51:18 · answer #1 · answered by Anonymous · 0⤊ 2⤋
Electricity goes through the filament, alternating direction with AC current. The MIDDLE of the filament is the location of greatest resistance, so that's where it heats up first, turns red and then white hot, giving off light.
It does not happen at the ends first because there is less resistance at the ends. It is the resistance to current (flow of electrons) that generates the heat and light.
2006-09-11 02:49:51 · answer #2 · answered by fiddlesticks9 5 · 0⤊ 1⤋
The electrical contact wires that lead to the lamp base provide a thermal path away from the filament, a heat sink. And because these wires are necessarily mounted to the ends of the filament, the center of the filament will heat quicker since it is at the point of highest thermal resistance.
WK
2006-09-11 05:24:30 · answer #3 · answered by olin1963 6 · 1⤊ 0⤋
The above answer is correct. It's the mounting posts for the filament.
2006-09-11 18:49:27 · answer #4 · answered by gp4rts 7 · 0⤊ 0⤋