SCIENCE plane mirrors, spherical mirrors, mirror equation

plane mirror

or a flat mirror

optical device with a flat surface that produces images through specular reflection

lateral inversion

apparent left to right reversal

lateral = sideways

inversion = reversal

types of images

real images

virtual images

real images

images that can be projected onto a screen

virtual images

type of images that cannot be projected onto a screen

four properties used in describing images formed in mirrors and lenses

1. type

2. size

3. alignment

4. location

size

larger vs. smaller

size of the image is always described in the comparison to the size of the object

alignment

upright vs. inverted

refers to the orientation of the image formed

upright

if the image is positioned the same way the object is positioned

inverted

if the image is oriented upside down compared to the object

location

described where the image is formed

can be determined by measuring the distance of the image

ray diagrams

illustrations that trace the path of light rays that form the image

law of reflection

in plane mirrors, light rays simply follow the ___

spherical mirrors

mirrors curved inward or curved outward

appear like a portion of a sphere

two kinds of spherical mirrors

concave mirrors

convex mirrors

concave mirros

spherical mirrors that curve inwards

also called converging mirrors

convex mirrors

spherical mirrors that curve outward

also called diverging mirrors

concave mirrors

called converging mirrors because all light rays parallel to the optic axis converge at the focus

ex:

satellite dishes

rules for using ray diagrams in convex mirrors

1. an incident light ray parallel to the optic axis is reflected appearing to pass through the focal point. broken lines can be used to trace the reflected rays to the focus

2. an incident light ray appearing to pass through the focal point is reflected parallel to the optic axis

3. an incident light ray appearing to pass through the radius of curvature is reflected in the same direction

mirror equation

1/do + 1/di = 1/f

do = distance of the object from the mirror

di = distance of the image from the mirror

f = focal length, half of the radius

ho = height of the object

hi = height of the image

di positive

image is in front of the mirror

REAL IMAGE

di negative

image appears to be behind the mirror

VIRTUAL IMAGE

f positive

focus is in the front of the mirror

CONCAVE MIRROR

f negative

focus is at the back of the mirror

CONVEX MIRROR

formula for convex when looking for di

di = fdo/do+f

formula for concave when looking for do

di = fdo/do-f

formula for f

f=dodi/(di+d)

m positive

image is upright

m negative

image is inverted