
In this picture, the daisy is yellow because it is being hit by white light and yellow light is reflected off the daisy. Red and Green light is really being reflected off the daisy because when you mix Red and Green light you get yellow. In your eyes, there are three cones that pick up Red, Green or Blue. Depending on the intensity of these three colors all colors can be made. This is how televisions and computer screens work.
In this picture, the ducks are swimming through the water and making waves. Since the duck is swimming faster than the wave it is creating it will all pile up in front of the duck. This piling of waves is called the Doppler effect. This happens with sound waves also. When a car moves toward you, the frequency changes because of the pile up of waves. Breaking the sound barrier was achieved when airplane designers put a point of the plane. Once an object moves faster than the sound waves it produces the waves make a v shaped behind the object. This is seen in the picture.