Curved Mirrors
Curved Mirror Terminology
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Like plane mirrors, curved mirrors still
follow the law of reflection, but, because
of their curvature, the rays are reflected at
slightly different positions.
Vertex – The middle point of a curved
mirror.
Focal Point – The point where light rays
meet or appear to meet.
Focal Length – The distance from the
vertex to the focal point.
Curved Mirror Terminology
Concave Mirrors
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A concave mirror has a reflecting
surface that curves inward like a
bowl.
AKA: Converging Mirror
The image formed by a concave
mirror depends on how far away the
object is away from the focal point of
the mirror.
Concave Mirror Diagram
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What happens to light rays that strike a concave mirror?
Focal Point
Vertex
Uses for Concave Mirrors
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Flashlight
Telescope
Car Headlight
Solar Oven
Image Terminology
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When it comes to describing an image in
a mirror – we have to be able to describe
it on several levels…
1.
2.
3.
4.
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Location – Where is the image?
Orientation – Upright or Inverted?
Size – Larger or Smaller?
Type – Real or Virtual?
The characteristics spell out the word
LOST!!!
You will need to get LOST for each
ray diagram you do for a mirror!!! 
Virtual vs. Real Images
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Virtual images are formed from
diverging light rays.
• Virtual images are tricky because are eyes
believe the image is being made from light
rays.
• Virtual images can not be projected on to a
screen.
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Real images are formed from the
convergence of light rays – the image is
made when light rays intersect each other.
• Real images can be projected on to a screen.
Images in Concave Mirrors
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This gets tricky…it all depends on how far
away the object is away from the mirror
itself.
There are four different outcomes for the
image type, position and orientation
based on each of the following:
1. Object more than two focal lengths away
from vertex.
2. Object is between 1 and 2 focal lengths away
from mirror.
3. Object is at focal point.
4. Object is between focal point and vertex.
Images in Concave Mirrors
Convex Mirrors
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A convex mirror is a reflecting
surface that curves outward.
AKA: Diverging Mirror
A convex mirror produces a virtual
image that is upright and smaller
that the object.
Convex Mirror Diagram
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What will happen to the light rays as they strike a convex
mirror?
Can we relate the reflected
rays in some manner?
Uses for Convex Mirrors
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Store Security
Side-view Mirrors
Images in Convex Mirrors
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What image of the candle will
appear in the mirror?
The Image is:
• Upright
• Smaller
• Virtual
Images in Convex Mirrors
Magnification
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Magnification is the measure of how much larger or
smaller the image is compared with the object itself.
Magnification is expressed as a ratio of the height of
the image to the height of the object.
Magnification = Image height
Object height
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Magnification can also be determined using the ratio
of the distance from image to mirror and distance
from object to mirror.
Magnification = Image distance
Object distance
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M = hi
ho
M = di
do
Make sure to use proper formulas and units when doing your
calculations.
THE END!!!