Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Date: Name: What is Light? 1. What is light? Light is a form of energy visible to the naked eye It is an electromagnetic wave 2. Three properties of light are: i) It travels in straight lines ii) It does not need a medium to travel through iii) Travels very fast What is the value of c? c = speed of light = 3.00 X 108 m/s 300 000 000 m/s 3. a) What is the electromagnetic (EM) spectrum? It is a range of radiant energy that travels as an electromagnetic wave b) Study the chart below showing the various forms of EM radiation. energy low wavelength long high short frequency low 1 2 3 4 Cycles per second c) Describe the visible spectrum ROYGBIV 4. What are some uses for the following electromagnetic waves? Type of Uses Electromagnetic Wave Radio Wave AM / FM Radio Radar TV signal Astronomy Cell phones Microwave Telecommunications Cooking Astronomy Infrared Light Remotes Food warming Lasers Physio heat detection high 5 Visible Light Ultraviolet Light X-Rays Gamma Rays Human vision Stage lighting Rainbows Sunburn increases risk of skin cancer Makes vitamin D in skin sterilizes water (kills bacteria) Black lights Medical imaging Security Cancer treatment Cancer treatment Produced in nuclear reactions 5. a) Define luminous and provide an example. Capable of Producing its own light e.g. Sun, candle, light bulb b) What is a non-luminous object? How can we see a non-luminous object? Does not produce its own light but reflects some frequencies of light that are captured by our eye (retina) 6. Describe the difference between transparent, translucent and opaque materials. Give examples. Transparent: Glass, Kool aid, coloured glass Light can pass through (you can read writing through it) Translucent: Grease spot on a paper bag Light can pass through but you cannot read writing through it Opaque: Light cannot pass through Curtains, walls, tree etc.