Unlocking the Mystery of Incandescent Lamp's Light Frequency

What determines the peak frequency of light emitted by an incandescent lamp?

a) Voltage applied to the lamp.
b) Gas used inside the lamp.
c) Material of the lamp's filament.
d) Temperature of the lamp's filament.

Answer:

The peak frequency of light emitted by an incandescent lamp is determined by the temperature of the lamp's filament.

The light at the peak frequency of an incandescent lamp depends on the temperature of the lamp's filament. This is due to the fact that incandescent lamps function by heating a tungsten filament until it glows. The temperature of the filament determines the color of the light emitted, since different temperatures correspond to different radiation frequencies according to the blackbody radiation principle.

Incandescent light bulbs work by converting electrical energy into light and heat as current flows through the filament. A filament heated to higher temperatures will emit light with a peak frequency that is higher, thus affecting the color of the light. Tungsten is used specifically because of its ability to emit a white light that contains virtually every frequency when heated to high temperatures.

Therefore, while factors like the voltage applied to the lamp and the material of the lamp's filament are relevant to the functioning of the lamp, it is ultimately the filament's temperature that is key.

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