• Question: is light a wave ?

    Asked by rapid.scientist to Mary, Loice, George, George, Diana on 4 Jun 2019.
    • Photo: George Makau

      George Makau answered on 4 Jun 2019:


      Light exists as massless particles (photons) which contain energy and momentum, but no mass, hence light is not considered as matter. (Remember the basic definition of matter as anything that has mass and occupies space)

      Light is the transfer of energy from a point of generation to another in a straight line via self-perpetuating electric and magnetic fields perpendicular to the direction of propagation. This pattern of energy transfer is what is called a wave. As the fields(and energy transfer) are moving like a wave, we can take light as a wave. Because the energy is delivered in fixed quantities(quanta) we can consider light as a particle.

      Simply put, light is not a matter but it is a wave and can be considered as a massless particle.