How is a light bulb related to radiation?

A light bulb is related to radiation because it emits light through the process of electromagnetic radiation. When an electrical current passes through the light bulb's filament (in the case of an incandescent bulb) or through a gas (in fluorescent lamps), the energy causes the filament or gas to heat up and produce light. This light is a form of electromagnetic radiation that is visible to the human eye.

Light bulbs primarily emit radiation in the visible spectrum, which is the range of electromagnetic radiation that can be detected by the human eye. However, they may also emit infrared radiation (which we feel as heat) and sometimes ultraviolet radiation (which we cannot see).

The process in an incandescent bulb involves heating the filament to a high temperature, generally made of tungsten, until it glows. The glowing filament radiates light in all directions. Most of the energy in an incandescent bulb is actually emitted as heat rather than visible light, making it less energy-efficient compared with other lighting technologies like LEDs or fluorescent bulbs, which have a different mechanism to produce light with less heat production.