70 Changes to ObamaCareâ¦ â So Far. By our count at the Galen Institute, more than 70 significant changes have been made to the Patient Protection and Affordable Care Act, at least 43 that the Obama administration has made unilaterally, 24 that Congress has passed and the president has signed, and three by the Supreme Court.
When a ray of light or a sound wave refracts or is refracted, the path it follows bends at a particular point, due to a change in the density of the substance it is passing th â¦ rough. For example if you put a pencil in a glass half full of water, the pencil looks like it is broken because the empty glass bends the light differently from the water.
refraction definition. A change of direction that light undergoes when it enters a medium with a different density from the one through which it has been traveling â for example, when, after moving through air, it passes through a prism. (Compare reflection.) Note: Lenses and other optical instruments work through refraction of light.