Gr. 10 Science Exam Study Guide PDF

11.1-11.4 Nature of light, EM Incidence light is not the same as incandescent light spectrum, types of light, lasers, 11.1 ray model, ways of producing light -light travels in straight lines medium-any physical substanc...

11.1-11.4 Nature of light, EM Incidence light is not the same as incandescent light spectrum, types of light, lasers, 11.1 ray model, ways of producing light -light travels in straight lines medium-any physical substance through which energy can be transferred -Other types of energy (heat energy) require a medium to transfer, while light energy travels through empty space, meaning it does not need a medium for transmission. electromagnetic wave-a wave that does not require a medium, and travels at the speed of light -light travels in electromagnetic waves -Electromagnetic waves are a type of radiation. radiation-a method of energy transfer that does not require a medium; the energy travels at the speed of light. -Light energy is transferred through radiation (travels in electromagnetic waves) electromagnetic spectrum- the classification of electromagnetic waves by energy -The electromagnetic spectrum consists of light listed according to its different energy levels. -The order from least energy to most energy is radio waves, microwaves, infrared light, visible light, ultraviolet light, X-rays, and gamma rays. visible spectrum-the continuous sequence of colours that make up white light -In a vacuum, each colour of the visible spectrum travels at the speed of light. -In a prism, colour travels slower than in a vacuum. -Within the prism, colour slows down to different speeds. This is why a prism can separate white light into different colours. 11.2 - ways light is produced Incandescence-the production of light as a result of high temperature Electric Discharge-the process of producing light by passing an electric current through gas Phosphorescence-the process of producing light by the absorption of ultraviolet light resulting in the emission of visible light over an extended period of time Fluorescence-the immediate emission of visible light as a result of the absorption of ultraviolet light Chemiluminescence-the direct production of light as the result of a chemical reaction with little or no heat produced Bioluminescence-the production of light in living organisms as the result of a chemical reaction with little or no heat produced Triboluminescence-the production of light from friction as a result of scratching, crushing, or rubbing certain crystals Light-Emitting-Diode (LED)-light produced as a result of an electric current flowing in semiconductors 11.3 Lasers -Consists of electromagnetic waves of exactly the same energy level. -Is a single, pure colour (e.g., red light remains red when passed through a prism). -Coherent: Waves travel in unison and in the same direction. - Highly concentrated in a narrow beam, able to travel great distances without spreading. Comparison to Ordinary Light: -Ordinary light sources emit waves of various energy levels and spread out in all directions. -White light separates into a spectrum of colours when passed through a prism. 11.4 -if light is radiating in all directions, there is an infinite number of light rays. But you only need to draw a few light rays to represent the overall picture light ray-a line on a diagram representing the direction and path that light is travelling geometric optics-the use of light rays to determine how light behaves when it strikes objects incident light-light emitted from a source that strikes an object transparent-when a material transmits all or almost all incident light; objects can be clearly seen through the material translucent-when a material transmits some incident light but absorbs or reflects the rest; of the objects are not clearly seen through the material opaque-when a material does not transmit any incident light; all incident light is either absorbed or reflected; objects behind the material cannot be seen at all image-reproduction of an object through the use of light mirror-any polished surface reflecting an image reflection the bouncing back of light from a surface -Most mirrors consist of two parts: The front part is a sheet of glass, and the back part is a thin layer of reflective silver or aluminum. incident ray-the incoming ray that strikes a surface reflected ray-the ray that bounces off a reflective surface normal-the perpendicular line to a mirror surface angle of incidence-the angle between the incident ray and the normal  the angle of reflection-the angle between the reflected ray and the normal 12.1 Refraction, normal, rules of -Refraction is the bending or change in the direction of light refraction when it travels from one medium into another medium. -Refraction occurs because light travels at different speeds in different mediums and bends when changing speeds when going into different mediums. -a normal is the line perpendicular to the surface of the medium where the incidence ray hits the end of the first medium -the angle of refraction is the angle between the refracted ray and the normal Rules of Refraction: 1. the incident ray, the refracted ray, and the normal all lie in the same plane. 2. The refracted ray bends towards the normal if it is slowing down in the second medium and away from the normal if it is speeding up in the second medium. - Light still follows the same path even if you switch its original direction. 12.4 index of refraction, n=c/v n=c/v is used to calculate the index of refraction v=c/n is used to calculate the speed of light in a medium -n=index of refraction -c=speed of light in a vacuum 3.00 x 10^8 m/s -v=speed of light in other medium -the index of refraction in air is 1 Index of Refraction: -The index of refraction is the ratio of the speed of light in a vacuum to the speed of light in a medium, n = c/v; this is also equal to sin