The reason we perceive a lemon as yellow has to do with the way light interacts with the lemon’s surface and how our eyes and brain process that information. Lemons have a skin that reflects certain wavelengths of light while absorbing others.
When light hits the surface of a lemon, it absorbs most of the colors in the spectrum except for yellow. This reflected yellow light is what reaches our eyes. Our eyes contain photoreceptor cells called cones, which are sensitive to different wavelengths of light corresponding to colors. The cones send signals to our brain, which interprets these signals as the color yellow.
Additionally, the perception of color is subjective and can also be influenced by surrounding colors and lighting conditions. In different lighting, a lemon might appear slightly different in color, but under normal daylight, the striking yellow hue stands out, affirming the lemon’s recognizable identity.