/sci/ - Science & Math

It's a form of radiation.

Electrons jump up their orbital levels due to increased energy. In the case of an incandescent bulb, they get more energy from heat caused by electrical resistance. When electrons fall back down into their natural orbital levels they have to release energy, and do so in the form of a photon. Different elements require different amounts of energy to raise an electron from its orbital, and consequently release different amounts of energy when the electrons fall back down. This differing in energy causes photons to be emitted at different frequencies, and thus different colors of light. Nitrogen, for example, will glow blue in the 470 something nm range (I think) when this occurs. The phenomenon is known as "spectra emission".

For the sake of simplicity, OP can just consider the photons to be small packages containing the energy, and electrons release them when they go from an excited (higher energy) state to a lower energy one.

Why do the electrons leave the excited state while the heating continues?

Nobody fucking knows.

Here's a suggestion OP, become a scientist and discover this so we'll all know.