• Question: how do lights work?

    Asked by cheese2000 to Faye, Martin, Mus, Pete, Adam, Amylou, Mark L, Samantha on 15 May 2012. This question was also asked by jamesgt01.
    • Photo: Faye Didymus

      Faye Didymus answered on 15 May 2012:

      Light is a form of energy that can be released by an atom. It is made up of many small particle-like packets that have energy and momentum but no mass. These particles, called light photons by scientists, are the most basic units of light. Atoms release light photons when their electrons become excited! Electrons are the negatively charged particles that move around an atom’s nucleus. An atom’s electrons have different levels of energy, depending on several factors, including their speed and distance from the nucleus. Electrons of different energy levels occupy different orbitals….generally speaking, electrons with greater energy move in orbitals farther away from the nucleus. When an atom gains or loses energy, the change is expressed by the movement of electrons. When something passes energy on to an atom, an electron may be temporarily boosted to a higher orbital (farther away from the nucleus). The electron only stays in this position for a tiny fraction of a second; almost immediately, it is drawn back toward the nucleus, to its original orbital. As it returns to its original orbital, the electron releases the extra energy in the form of a photon, in some cases a light photon. The wavelength of the emitted light (which determines its color) depends on how much energy is released, which depends on the particular position of the electron. So, the color of the light is determined by what kind of atom is excited. This is the basic mechanism at work in nearly all light sources…I hope it helps to answer your question 🙂