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Mirrors. Plane and Spherical. Plane Mirrors. Flat mirrors. Which type of image? Virtual We perceive the image at point I where the ray extensions intersect. Image of Penny. Real Penny. Clifton Bluhm. Curved Mirrors. http://www.waitingtimetoys.com/wallmodels.2/fun.mirror.html.
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Mirrors Plane and Spherical
Plane Mirrors • Flat mirrors. Which type of image? Virtual We perceive the image at point I where the ray extensions intersect
Image of Penny Real Penny Clifton Bluhm
Curved Mirrors http://www.waitingtimetoys.com/wallmodels.2/fun.mirror.html http://www.throwlikeagirl.net/archives/000040.html
FocalPoint Principle Axis FocalLength (cm)
http://www.atnf.csiro.au/news/press/images/urumqi/urumqi_25m_telescope.jpghttp://www.atnf.csiro.au/news/press/images/urumqi/urumqi_25m_telescope.jpg
Arecibo Radio Telescope http://www.windows.ucar.edu/earth/images/arecibo.jpg Diameter = 305 m (1000 ft) Built = 1963Location = Puerto Rico
Focal Length of a Spherical Mirror R – Radius of Curvature
Ray Tracing We will predict the image that will be formed by a mirror or lens using ray tracing. We typically care about three ‘special’ rays: • Two rays that go through the focal points • The ray that go through the center of the object
Spherical Mirrors and Ray Tracing The focal point of a concave mirror The focal point of a convex mirror Slide 18-32
Three Sets of Special Rays for a Concave Mirror Slide 18-33
A Real Image Formed by a Concave Mirror Slide 18-34
Three Sets of Special Rays for a Convex Mirror Slide 18-36
Ray Tracing for a Convex Mirror Slide 18-37
Images and Mirrors • Real images will form on the side of the mirror where the object is located • Virtual images will form on the opposite side
The Thin-Lens Equation – This works for both mirrors and lenses Thin-lens equation (also works for mirrors) relating object and image distance to focal length Slide 19-10
Sign Conventions for Lenses and Mirrors Slide 19-11
Magnification A random place for this slide but it needs to go somewhere. The next slide shows the different values from this equation. Slide 18-26
Ray Tracing: Virtual Images Slide 18-27
Sample Problem A convex mirror has a focal length of -10 cm. An object of 4 cm high is placed 20 cm in front of the mirror. • Find the position and size of the image. • Describe the nature of the image.