why is tungsten used for light bulb filaments?

Question

detailed answers appreciated loads its for homework plz help thx

Answer 1

It was found by trail and error to be the best material. This includes the light that it would give off and the ability to last longer than other materials.

It was really a compromise. They had to also take into account the cost of the filiment. There were even light bulbs made using Platinum but as you can imagine the cost would be far to high. Tungsten was found to be the best compromise between function, reliability and cost.

Since there have been better inventions like the Halogen bulbs and the Flourecent bulbs. But Tungsten was the best for the incandesent bulbs invented by Thomas Edison.

Hope this helps

Answer 2

Tungsten is a heating element. The electricity (electrons in motion) heat up the thin tungsten filiment and the electrical energy is converted to light. The actual light bulb is sealed to prevent the outside air from oxydizing or ultimately destroying the filament. Like all commercial materials, the reason for using tungsten is probably due to its durability, heat resistance, and its efficiency in releasing photons from an electrical charge.

Answer 3

Heat is generated when electricity passes through a substance. At a similar power level, for a greater resistance more heat can be expected to be generated. Things that affect resistance are ambient temperature, wire size (length and diameter) and what the wire is made from (elements and number of conductors.) Items like toasters, ranges and older light bulbs used materials designed to create resistance. Large power conductors are designed with insulation, a thickness and a good conductor to keep resistance to a minimum. There are formulas that will calculate resistance. But because there is about 7% inefficiency in the US transportation grid we can assume about 7% of the total electricity produced in the US is being converted into heat. That amounts to a tremendous amount of heat. We don't notice it because it is released into the free air and it is spread out over long distances and many wires so the actual chance in temperature in any one place is not as much as in the light bulb. (which are only about 5% efficient at producing light and 95% efficient as a heater)

Answer 4

Tungsten is used as filament in electric bulbs b'coz, it has very high melting point, its reactivity with chemicals is also very less. It can resist high temperature..

Answer 5

Hi. Because it has such a hight melting point and can get very hot. It can also be formed into a filament.