Light

5.1 UNDERSTANDING REFLECTION OF LIGHT
1. Reflection of light on a Plane Mirror

Mirror works because it reflects light.. The light ray that strikes the surface of the mirror is called incident ray. The light ray that bounces off from the surface of the mirror is called reflected ray. The normal is a line perpendicular to the mirror surface where the reflection occurs. The angle between the incident ray and the normal is called the angle of incidence, i The angle between the reflected ray and the normal is called the angle of reflection, r.

2. Laws of Reflection

1. The incident ray, the reflected ray and the normal all lie in the same plane. 2. The angle of incidence, i, is equal to the angle of reflection, r.

3. Draw ray diagrams to show the positioning and characteristics of the image formed by a plane mirror.

4. Describe the characteristics of the image formed by reflection of light..

1. laterally inverted, 2. same size as the object, 3. virtual 4. upright 5. as far behind the mirror as the object is in front of it. Notes: Real image : Image that can be seen on a screen Virtual image : Image that cannot be seen on a screen.

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Reflection of light on curved mirror

Convex mirror Concave mirror Common terminology of curved mirrors Centre of curvature, The center of sphere of the mirror C Principle axis The connecting line from the centre of curvature to point P Radius of curvature, The distance between the centre of curvature and the surface of CP the mirror. Focal point, F The focal point of a concave mirror is the point on the principle axis where all the reflected rays meet and converge. The focal point of convex mirror is the point on the principle axis where all the reflected rays appear to diverge from behind the mirror. Focal length, f The distance between the focal point and the surface of the mirror. (FP or ½ CP) Object distance, u Image distance, v The distance between the object and the surface of the mirror. The distance...