Electric bulb filament ?why does it get red at the middle first & not the ends?

Question

when electric Current flows thru fillament?

Answer 1

This diagram shows that the middle glows red because it is made of a different material (tungsten) then the rest of the filament (copper). Different materials glow at different temperatures.

http://www.goodmart.com/facts/light_bulbs/incan_diagram.aspx

Answer 2

Electric bulb filament gets red at the middle first and not the ends because the supports at the ends conduct away some of the heat.

Answer 3

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.