Law of Reflection
Analysis of an image in a plane mirror, Two Methods
Method 1 |
Method 2 |
|
Example |
Text Book p686 Fig 23-6 - Reproduce this diagram in
your notes |
Downloadable handout - Reflected Images in Plane Mirrors
also p687 fig 23-7 |
Object |
Consider the object as a single point. |
The object is often depicted as an arrow. In the analysis
the top of the arrow and the bottom of the arrow usually each analyzed.
|
Eye |
The eye is depicted larger than a single point and
often in a larger than realistic scale. consider one ray going into the
top of the iris and one ray going into the bottom of the iris in the analysis.
|
Consider the eye as a single point. |
Method |
Consider two incident rays emanating from an object and striking a plane mirror. Draw both reflected rays such that they behave in accordance with the law of reflection. Project the reflected rays back behind the mirror surface using dashed lines. Where the virtual rays converge is the location of the virtual image. |
Generate an incident ray from the top of the arrow
and another from the bottom of the arrow, both reflect in accordance with
the law of reflection in such a way that the reflected rays converge at
the eye. Project back virtual rays behind the mirror surface with dotted
lines. Use do=di and the location of the virtual rays locate the virtual
image. Draw the virtual image in dashed lines. note 2 - solutions to the handout |
What this Demonstrates |
This shows that di=do, and the image is virtual. |
This shows ho=hi (height of object = height of image,
no magnification of image), image is oriented upright (it is not inverted)
and image is virtual |
Characteristics of Images