Chapter 23 Light

Chapter 23

23.1 Ray Model of Light

Light travels in straight lines

Ray model of light - light travels in straight line paths called rays

geometric optics - straight line rays reflect at various angles

light can be absorbed, reflected or pass through objects

Chapter 23

23.2 Reflection

Light reflected off object– angle of incidence– angle of reflection

Law of Reflection– angle of incidence

equals the angle of reflection

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diffuse reflection - light reflected in many directions due to rough surfaceplane mirror page 686 fig 23-6virtual image - brain interprets any rays entering eye as following a straight line pathimage distance = object distanceExample 23.1 mirrorExample 23.2 photo

Chapter 23

23.3 Spherical mirrors

convex - reflecting surface on outer surface of sphere demagnified - wide field of view

concave - reflecting surface in inner surface of sphere - magnified image

focal point - rays from a concave mirror meet at a single point

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figure 23-13 principle axis beyond focal point - image inverted

focal length - distance between focus and center of mirror

convex mirror - focal point is at F behind mirrorfigure 23-17

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23.5 Refraction : Snell’s Law

Light passing from one medium to another

figure 23-18

ex. 23-8 refraction through flat glass

ex. 23-9 depth of pool

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23.6 Fiber Optics

total internal reflectionglass and plastic fibers as thin as a few micrometerslight can be transmitted along it with almost no lossesfiber optic cables - telecommunications & medicinemodulated light beam - transmitted at a higher rate and with less loss and interference than an electrical signal

Chapter 23