Objectives:

     1.  Students will be able to identfy plane, convex, and concave mirrors
     2.  Students will be able to distinguish between virtual and real images
     3.  Students will be able to solve for the focal point of mirrors
     4.  Students will be able to solve for the magnifiaction of mirrors

Real life application:

• Plane mirrors are used everyday to reflect images of a person or object.
• Convex mirrors are used at the corners of hallways to view who is coming down the intersecting hallways
• Concave mirrors are used in telescopes to enlarge images that are far away.

    Law of Reflection~  If a ray of light approaches a flat mirror, then the behavior of the light as it feflects would leave the mirror with an angle equal to that of the incident ray.

    Plane Mirror~
      1.  The image is upright.
      2.  The image is the same size as you are.
      3.  The image is virtual.
      4.  There is no focal point.
      5.  The image is located as far behind the mirror as you are in front of it.
 
 

    Virtual Image-the image is right side up
    Real Image- the image is up side down
Convex Mirror~ 
      1.  The image is distorted.
      2.  The image is virtual.
      3.  The mirror curves out.
      4.  Size of image and object is the same.
      5.  Negative focal point because image is virtual.

    Concave Mirror~ 
      1.  Mirror curves in.
      2.  Creates a real image.
      3.  Focal Point is in front of mirror.
      4.  Images are smaller unless the object is between the focal point and the mirror, then the image is enlarged.

Formulas:

                         1 _ 1 = 1
              f    d_o    d_i

    _{f=focal point
    do=distance of object (cm)
    di=distance of image (cm)}

    _{magnification= di
                                              do}

_Examples:

_{1.  A 6 cm light bulb is placed at a distance of 37.3 cm from a concave mirror having the focal distance of 10.8 cm.  Determine image distance and magnification.}
1 _ 1 = 1          1 _ 1 = 1      d_i = 15.201 cm
f   d_o     d_i                10.8  37.3    d_i

_{magnification= di           15.201cm  =  .4075 X
                    do             37.3 cm}

_{2. A 30 cm tall Christmas tree was placed in front of a convex mirror 70 cm away.  The focal distance is -57.6 cm.  Solve for the image distance and magnification.}
1 _ 1 = 1          1 _ 1 = 1      d_i = -31.5987 cm
f   d_o      d_i               -57.6   70      d_i

_{magnification= di           -31.5987cm  =  -.4514 X
                    do             70 cm}

_{3.  A 2 cm tall ant was put in front of a caoncave mirror 500 cm away.  the focal distance was 27 cm.  Solve for the image distance and manification.}
1 _ 1 = 1          1 _ 1 = 1      d_i = 28.541 cm
f   d_o      d_i                 27    500    d_i

_{magnification= di           28.541cm  =  .05708 X
                    do             500cm}
 

_{Photos courtesy of: The Physics Classroom}
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