Unit 3 Lesson 9 Color--
Rainbows are a result of sunlight reflecting and refracting through raindrops that act like a prism, separating out visible light waves by their wavelengths. Violet and red light refract at sharp angles compared to blue and green light. Thus, as the white light separates, you see all the colors of the rainbow
- Why do you see different objects as different colors? For instance, why do you see grass as green? You see objects as different colors because some light waves are absorbed while others are reflected. Grass is green because it absorbs red, orange, yellow, blue, indigo, and violet, but reflects green. These green light waves are what your eyes detect, and so you can see grass.
- What happens when you mix primary colors of light? When you mix primary colors of light, which are red, green, and blue, you can see all the other colors.
- Why do you see the primary pigment color yellow? Primary colors are a result of light waves that are reflected and interpreted by your eyes. You can see yellow pigments because it absorbs blue light and reflects red and green light. When these red and green light waves overlap, your brain intercepts them as yellow. The primary pigment colors are cyan, magenta, and yellow.
Dispersion is when white light separates into colors
Unit 3 Lesson 10 Sources of Light--
Incandescent Light- Light bulb that has a wire and lights up when electricity passes through it. Air has been removed from the inside of the light bulb so the light will stay. Light that is produced when it gets hot enough.
Fluorescent Lights- Filled with gas that gives off ultraviolet light when electricity passes through it. In a process called fluorescent, a material absorbs light at one wavelength and then emits light at a longer wavelength. Fluorescent light bulbs emit light by causing phosphor to steadily emit protons.
Laser- a device that generates a beam of coherent light. Laser light is emitted when excited atoms of a solid, liquid, or gas emit photons.
Sodium Vapor Light-- As electric current passes through a sodium vapor bulb, it ionizes the gas mixture. The mixture warms up and the heat causes the sodium to change from a solid into a gas.
