One the most effective treatments for SAD is light therapy, often combined with antidepressants and talk therapy. Sitting in ...

It includes light waves from gamma rays to radio waves. Each carries energy and moves at the speed of light. As the following diagram shows, the energy of the wave increases as the wavelengths become ...

The light travels in a straight line directly from the object to your eye. Ray diagrams are used to show the path that light takes. The rays of light are represented using straight lines ...