Curved Mirrors:Locating Images in Concave & Convex Mirrors
Concave & Convex
Curved Mirrors: Terms You Should KnowCentre of Curvature, CIf you draw a series of lines at right angles to a curved mirror, they will meet at 1 point this is the centre of curvature.2. Principal AxisThis is a line that goes through the centre of the mirror and is used to help us draw images.3. Vertex, VThe point where the principal axis and the mirror meet.
Curved Mirrors: Terms You Should Know4. Focal Point, FIn a curved mirror, an incident ray that is near and parallel to the principal axis when reflected, will cross the principal axis at a point called the focal point, or F
5. Focal LengthThe distance between F and V
Note: C is always 2x farther from the mirror as F
Curved Mirrors: Label this diagram!VertexPrincipal AxisFocal PointCentre of CurvatureFocal Length
Drawing Ray Diagrams to Locate Images in Concave MirrorsStepsDraw the object, so the bottom of it is on the principal axis.The image will also be on the principal axis, which means we only need to find the top of the image!We only need to draw 2 incident rays, without measuring angles
Concave Mirror Ray DiagramsRay 1Draw an incident ray near and parallel to the principal axis The reflected ray will go through F
Ray 2Draw an incident ray through F This will reflect parallel to the principal axis
Ray 3An additional ray can be drawn through CThis ray will reflect back on itself
Finding the ImageJust like in plane mirrors, to find the image in a curved mirror we simply trace the reflected rays back until they meet.The point where they meet will be the top of the image!
We can describe images in concave mirrors using the SALT method. The characteristics of an image in a concave mirror will depend on the location of the object.
Lets Try it!Image Attributes:S = SmallerA = InvertedL = Between C & FT = Real
Convex MirrorsWhen you shine rays of light parallel to the principal axis, the reflected rays travel out and away from each other (they diverge).Convex mirrors = divergent mirrorsBecause of this, the focal point (F) is convex mirrors is behind the mirror.We still use C, V & the principal axis to help us find images in Convex Mirrors
Concave vs. Convex Mirrors
Concave vs. Convex Mirrors
Drawing Ray Diagrams to Locate Images in Convex MirrorsStepsUse the same three incident rays you used in concave mirrors to find the image in convex mirrors.Characteristics of the ImageWe use the SALT method to describe images in convex mirrors There is only one image in convex mirrors
Lets try it!Image Attributes:S = SmallerA = InvertedL = Between C & FT = Virtual