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Reflection and Mirrors. Law of Reflection. Q i = Q r. A. B. A. B. Hero of Alexandria. "Principle of least distance". How does a ray "know" which path to follow?. All “incorrect” paths are longer!!. Flat Mirrors “Ray Tracing”. What size mirror do you need?.
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Law of Reflection Qi = Qr
A B A B Hero of Alexandria "Principle of least distance" How does a ray "know" which path to follow? All “incorrect” paths are longer!!
What size mirror do you need? Question: Does your distance matter?
Some Physics of Metals Metals conduct electricity because electrons can move around. Electrons re-arrange themselves to prevent a light wave from entering the surface of the metal. In non-conducting materials, electrons are tied to a positive charge and are not free to roam through the material.
Why the Different Colors? Silver - essentially all colors are reflected Gold - does not reflect blue; reflected light looks reddish-yellow Copper - does not reflect blue or green; reflected light looks reddish in color
Spherical Mirrors Shaving/makeup mirrors Telescopes Car side-view mirrors Spoons, pots, etc.
Spherical Mirrors F - focus of mirror C F C – center of curvature
Image Formation-Concave Incoming ray parallel to axis reflects through the focus O C F Image Ray through the focus reflects parallel to the axis Mirror reflects to the left
Image Formation-Concave O F C As the object gets farther away, the image appears closer to the focus.
Image Formation-Concave I O C F If the object is inside the focal point, The image will be virtual and upright.
Image Formation-Convex (truck appears far away) O F C Mack truck Demagnified image,