Thin Lens Chapter 15.2. Bending of Light Any transparent object that is curved with affect the path of light rays. Ex: o Glass bottle full of water will

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Thin Lens Chapter 15.2 Slide 2 Bending of Light Any transparent object that is curved with affect the path of light rays. Ex: o Glass bottle full of water will affect the image of an object. o Your eyes muscles expand and contract causing the lens in your eye to change shape and therefore allow people to focus on different objects. Slide 3 Lens Lens A transparent object that refracts light rays, causing them to converge or diverge to create an image. Slide 4 Converging Lens Converging Lens A lens where the middle part of the lens is thicker than the rim. Also known as a convex lens. Slide 5 Diverging Lens Diverging Lens A lens where the middle part of the lens is thinner in the middle and thicker around the rim. Also known as a concave lens. Slide 6 Focal Length Each lens has two focal points (F), therefore there are two focal length (f). A focal length is measured from the focal point to the center of the lens (normal). The focal points lay on the principal axis. Slide 7 Converging & Diverging Focal Points For converging lens, the focal point is located at the point where the rays of light meet at a single point. For diverging lens, the focal point is located at a point from which the diverged rays appear to originate. Slide 8 Rules For Drawing Ray Diagrams of Converging Lens RayFrom object to lensFrom lens to image Parallel RayParallel to Principal AxisPasses through focal Point Central RayTo the center of lens (Where normal meets principal axis) Straight through from the center of the lens Focal RayPasses through front focal point Parallel to principal axis Slide 9 Ray Diagrams for Converging Lens Slide 10 Slide 11 Slide 12 Rules For Drawing Ray Diagrams of Diverging Lens RayFrom object to lensFrom lens to image Parallel RayParallel to Principal AxisDirected away from front focal point Central RayTo the center of lens (Where normal meets principal axis) Straight through from the center of the lens Focal RayProceeding towards back focal point Parallel to principal axis Slide 13 Ray Diagrams for Diverging Lens Slide 14 Characteristics of Converging Lens Image is always real, unless object is in front of the focal point. Image is always on the opposite side the lens, unless the object is in front of the focal point. Image is always inverted, unless object is in front of the focal point. Slide 15 Characteristics of Diverging Lens Image is always virtual (Imaginary). Magnification is less than 1. Image is always upright. Image is formed on the same side as the object. Slide 16 Thin-Lens Equation Slide 17 Magnification Equation Slide 18 Example Problem An object is placed 30.0cm in front of a converging lens that has a focal length of 10.0cm. Find the image distance and magnification. Slide 19 Example Problem Answer