24 geometric optics
DESCRIPTION
24 Geometric Optics. Water drop as a converging lens. Reflection at a Plane Surface. Image and Object Rays diverging from one point P (object) recombine at point P’ by mirror or lens— an image formed. Object & Image Distances. Object distance Image distance Real image Virtual image - PowerPoint PPT PresentationTRANSCRIPT
24 Geometric Optics
Water drop as a converging lens
Reflection at a Plane Surface
Image and ObjectRays diverging from one point P (object) recombine at point P’ by mirror or lens— an image formed.
Object & Image Distances 1. Object distance2. Image distance3. Real image4. Virtual image5. Magnification
Sign Ruless: The (real) object distance is positive. (The distance is negative for a virtual object.) s’: The image distance (s’) is positive for all real images and negative for virtual images. y and y’: Heights are positive if measured upward from the principal axis and negative if measured downward. m: Magnification is positive if the image is erect and negative when inverted. f: The focal length is positive for converging mirrors and lenses, and negative for diverging ones.
Reflection at a Spherical Surface
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Focal Point & Focal Length-Concave
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Image Construction—Concave
Focal Point & Focal Length-Convex
Image Construction—Convex
Image Construction—Principal Rays
Image Construction—Practice
Refraction at a Spherical Surface
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How Deep is the Pool?
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Thin Lenses—Converging
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Thin Lenses—Diverging
Thin-Lens Equations
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Imaging thru Thin –Lens: Principal Rays
http://www.mtholyoke.edu/~mpeterso/classes/phys301/geomopti/lenses.html
Principal Rays: Practice
Summary: Reflection at a Plane Surface
Summary: Reflection at a Spherical
Surface
Summary: Graphical Methods for Mirrors
Summary: Refraction at a Spherical Surface & Thin
Lenses
Summary: Graphical Methods for Lenses
Example: The Eye’s Lens
The least distance of distinct vision (LDDV): 25 cm ~ 10 in
Mirror/Lens Equation
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LensThin
(-)convex or )( concave
mirror plane
Homework Ch24Problems:: 1, 4, 5, 6, 13, 20, 29, and 32
Answers to multiple choice problems
quiz(1) Construct the images using principal rays for a converging lens and a convex mirror, respectively. (2) Find the locations of images using lens/mirror equation (f = +5 or -5 cm, s = 8 cm).
Test 3 Grade Distribution
# of Students: 30Average: 12.8=64%
Test 3 Grade Distribution# of Students: 21Average: 11.7=59%