Unformatted text preview: Note that the negative sign implies that the image is a virtual image and not a real one. Figure 42: The Apparent Image Behind the Mirror. Figure 43: Using Rays to Locate the Image 15.2 Spherical Mirrors Spherical mirrors are a little more complicated than plane mirrors. Our goal is still to relate the object distance to the image distance, but we must first talk about how to tell one spherical mirror from another. A spherical mirror is essentially a cutout of a big sphere (hence the name), so its major distinguishing characteristic is its radius of curvature. For concave mirrors, we will say that the radius of curvature is positive and for convex mirrors we will sat that the radius of curvature is negative. The focal point of a spherical mirror is given by f = 1 2 r and takes the same sign as the radius of curvature. The focal point means different things for convex and concave mirrors. For concave mirrors, all rays coming in parallel to the central axis will reflect off of the mirror through the focal point. For convex mirrors, all rays coming in parallelwill reflect off of the mirror through the focal point....
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- Spring '08
- Physics, focal point, ray tracing, spherical mirror, spherical mirrors