Hello Forum, Awhite background reflects all colors (i.e. all incident wavelengths). A black screen, being black, absorbs all incident types of light (i.e. absorbs all incident wavelengths). a)Let's consider a red monochromatic beam projected on a black screen inside a dark room. Would the screen still look black (since it absorbs the red light) where the beam is projected or does it depend on the intensity of the red light? b) What if the room was illuminated by the presence of white sunlight? Would the screen region illuminated by the red beam still look black because all the incident light, regardless of its color, will By the way, black is not really a color in the sense that the "black" color is produced when no photons reach our eye. Grey is a brighter black. A grey surface absorbs all incident wavelengths but not as much as a black surface. Thanks!