Notes about Light Light energy travels in a straight line from its source. Light can travel through empty space where there is no air. Light travels very quickly (300,000 km/sec) but it slows down as it passes through water and glass. We cannot see all light waves. Visible light falls in the middle of the spectrum and is made of up Red, Orange, Yellow, Green, Blue, Indigo, and Violet (Roy G Biv) The light we see is considered white light. It is made up of all the colors of the rainbow. Light can, however, pass through materials that separate the colors. A good example of this is a prism. Light can be absorbed (taken in by an object), transmitted (passes through), reflected (bounces back) or refracted (bends). Light rays are reflected at the same angle that they hit. Light is refracted (bent) as it passes through lenses and water. Eyeglasses, contacts, microscopes, overhead machines, telescopes and cameras all use lenses that refract light rays. Light passing through is refracted. Light not passing through is reflected. Light taken in is absorbed. When light passes through something, its direction CAN change and the speed will slow down.