Mirrors II Concave Mirrors

Yesterday’s Review 0 Law of reflection is: the angle of incidence is equal to the angle of reflection, or, θ i = θ r 0 Plane mirror characteristics: 0 Object size = image size 0 Object distance = image distance 0 Always forms a virtual image (the image cannot be projected onto a screen) 0 Image is reversed

Yesterday’s Review 0 Plane mirror drawings: 0 How did you draw the images in the plane mirror from yesterday? 0 Question 7 – How is it done?

Goals for the day 0 Be able to draw a ray diagram for a concave mirror 0 Know the location & orientation (right side up or upside down) of images in concave mirrors 0 Be able to communicate using appropriate terminology such as: angle of incidence, angle of reflection, normal, centre of curvature, focus, & principal axis

Curved Mirror Terminology 0 Center of curvature (C): the center of the circle where the mirror represents a small arc 0 Focus (F): the point where parallel light rays converge; the focus is always found midway between the point where the principal axis cross the mirror 0 Principal axis (PA): a line drawn through the center of curvature, the focus, and the mirror upon which the object rests

Characteristics of Concave Mirrors 0 Concave mirror characteristics can differ depending on where the image is located in comparison to C and F 0 L.O.S.T. can be used to remember what characteristics to look for: 0 L is for relative location 0 O is for orientation (upright or upside down) 0 S is for the relative size of the image to the object (bigger, smaller, or same size as the object) 0 T is for type of image (either real or virtual)