• Question: what is light?

    Asked by to Mark, Matthew, Mike, Paul, Sabina on 17 Mar 2014. This question was also asked by .
    • Photo: Matthew Malek

      Matthew Malek answered on 17 Mar 2014:

      Wow — such a simple question, just three words, with such a complex answer!

      Light is many things. It is:

      – Responsible for carrying the electromagnetic force, one of the four fundamental forces of our universe.

      – A quantum packet of energy called a photon, which can behave light waves in certain situations and like particles in others.

      – A spectrum of energies and frequencies, encompasing everything from the visible light that we see to the microwaves that heat your food (cooking with light! Isn’t science wonderful?) to the x-rays that image our bodies to the radio waves used for mobile phones and TV/radio transmission. It also includes dangerous ultraviolate rays from the Sun, thankfully these are mostly blocked by Earth’s atmosphere, and interesting gamma rays from space!

      So there’s a very general overview answer for you. Hope it helps! If there are more specific things that you want to know about light, do feel free to ask other questions!

    • Photo: Mike Lee

      Mike Lee answered on 17 Mar 2014:

      Electrons are tiny particles which are charged – this means they don’t like to be next to each other. Imagine I have some electrons in my hand and shake them side to side. If you had some electrons in your hand the electrons would try and move your hand side to side as well. This is because moving electrons make ripples, and these ripples are what light is.

      If the shaking is fast enough – 600 million million shakes a second, these ripples become visible to the human eye.

Comments

  • ellenh commented on :

    thank you very much the answers you gave were really helpful and i feel like i have a much better understanding of the topic now. thanks! 🙂

    • Photo: Matthew

      Matthew commented on :

      Hiya, Ellen!

      Thanks for commenting. I do a lot of outreach work, and its great to get feedback like yours saying that my efforts helped you to understand something. After all, that’s why we do outreach and it feels fantastic to know that it is helping people.

      You’ve got three of us left to answer questions, and two more days to ask. Is there anything else about light (or anything else) that you want to know? 🙂