Figure 1. The law of reflection states that the angle of reflection is equal to the angle of incidence.

normal

Figure 2. Specular versus diffuse reflection.

ReflectionThe Law of ReflectionWhen a ray of light reflects off a surface, the angle of ___________ is equal to the angle of ___________. This relationship can be described mathematically as:

θr=θi.

Smooth vs. Rough Surfaces When light rays reflect off of a smooth surface, they do

so in the same pattern as the ___________ rays. o This produces a ___________ image.

When light rays reflect off of an irregular or dull surface, the pattern of reflected rays is ___________ than the pattern of incident rays.

o This produces a __________ or unclear image.

AnglesComplete the activities on this website to practice measuring angles with a protractor:

http://www.mathsisfun.com/geometry/protractor-using.html

What’s that law again? ___________ reflection occurs when light is reflected off a smooth shiny surface Because light travels in straight lines;

o The angle that light strikes the surface (__________________________) is the same as the angle that light leaves the surface (__________________________).

Terminology_________________: light which travels towards the mirror__________________: light which is reflected by (bounces off) the mirror___________: imaginary line drawn at 90 degrees to the mirror surface________________________: angle between the incident ray and normal________________________: angle between the reflected ray and normal

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Figure 3. Virtual image produced by a plane mirror.

DiagramDraw a diagram to explain the law of reflection in the space below.

Law of Reflection1. The angle of reflection ____________ the angle of incidence.2. The incident ray, reflected ray and normal all lie in the same _____________.

Real or Virtual Image?In plane mirror reflection, a _____________ image is formed. A _____________ image is an image formed by rays that do not actually pass through the location of the image.

Image CharacteristicsIn optics, we will describe the characteristics of an image using the acronym L.O.S.T.L - ______________O - ______________ (upright or inverted)S - ______________ (magnified, reduced, same size)T - ______________ (real or virtual)

In the table below, write a summary of the image characteristics for a plane mirror.

L

O

S

TFigure 1. Image characteristics for a plane mirror.

HomeworkComplete any parts of the Multiple Images lab not finished during class and make sure you fill out the table above.

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