• Question: How does light travel?

    Asked by BossBob1234 to Chloe, Irene, Pierre, Ricardo, Uday on 16 Nov 2015.
    • Photo: Uday Bangavadi

      Uday Bangavadi answered on 16 Nov 2015:

      Light is Electromagnetic wave. Which consists of Electric and Magnetic field. A time varying electric field produces a spatially varying magnetic field and a time varying magnetic field produces a spatially varying electric field. This varying electric and magnetic fields causes light to propagate on its own.

    • Photo: Irene Regan

      Irene Regan answered on 16 Nov 2015:

      Light travels as a wave. But unlike sound waves or water waves, it does not need any matter or material to carry its energy along. This means that light can travel through a vacuum—a completely airless space.

    • Photo: Pierre Casaubielh

      Pierre Casaubielh answered on 17 Nov 2015:

      An initial to describe the travel of light is by rays: for example, it goes from the sun to the earth and other planets.

      However it is an Electromagnetic wave, being described as having an electric and magnetic components.
      In presence of object, the light can modify his trajectory on the edge; there are a lot of similarities between optical, acoustic and ocean waves.

      Light can be reflected, diffracted, refracted by object …
      The properties of the light can also be modified… e.g. we can change its colour.

    • Photo: Chloe Huseyin

      Chloe Huseyin answered on 17 Nov 2015:

      Light travels really fast! Light travels at 299792458 metres per second… To put this into perspective… A person, moving at the speed of light, would circumnavigate the equator approximately 7.5 times in one second.

    • Photo: Ricardo Segurado

      Ricardo Segurado answered on 17 Nov 2015:

      People talk about light as waves, but they also talk about light particles, called photons. You could imagine these as little bullets of light shooting around the place.

      They are so small that we can’t see exactly what they are, but from careful experiments and a lot of maths you can show that light behaves as if it’s a wave and a particle, depending on the experiment you do. Spooky.