2.0 Light behaves in predictable ways.
(page 188-211)
GO#2: Investigate the transmission of light and describe its behavior using a
geometric ray model
a) investigate how light is reflected, transmitted, and absorbed by different materials;
and describe differences in the optical properties of various materials
OPTICAL DEVICES: are mechanisms that direct light beams to the viewer’s
eyes
through reflection and refraction.
OPTICAL SYSTEMS: consists of four elements: lenses, mirrors, prisms and a
light
source. YOU WILL LEARN ABOUT EACH TYPE AND HOW LIGHT IS
AFFECTED BY THEM AS YOU WORK THROUGH THIS TOPIC.
LAB A: TWISTED RAYS:
Read “Give it a Try” on page 175. Use the materials already set out.
Diagram what you see
Any possible explanation for what you saw?
LAB STATION B: BROKEN PENCIL?
1. Look at the pencil in the beaker.
Move down so you can look directly in the
side of the beaker.
Record what you see
(use pictures and words)
2. Look at the pencil in the beaker half full of water.
View it from the side
again and record what you see.
(use pictures and words)
Any possible explanation for what you saw?
LAB C: MAKE A PINHOLE CAMERA
Read the directions on page 185. Make your own camera or use one
already made to save time.
Diagram what you saw of the light bulb
when you looked through the camera.
Wax paper
Any possible explanation for what you saw?
LAB D: DESK DUTY:
2.1 LIGHT TRAVELS IN RAYS AND INTERACTS WITH MATERIALS (page
190)
RAY DIAGRAMS:
1. Define what predictable means.
2. A ________ _____________________ shows how light travels. The rays are
drawn
in ___________________ lines from the source of light.
3. Why are ray diagrams incomplete?
4. Draw two pictures below showing how ray diagrams can help explain why
light intensity (brightness) changes with distance from the source.
high intensity
_____ of light rays
reaching
the eye.
low intensity
_____ light rays reaching
the eye.
5. Draw a ray diagram below to show how shadows are created.
6. Where would you have to stand in relationship to the light source to create a
very large shadow compared to a small one?
LAB E: LIGHT INTERACTS WITH MATERIALS:
1. Shine a light source (light bulb) through the three different objects at this
station.
2. What happened to the light rays for each material?
LAB F: LIGHT INTERACTS WITH MATERIALS:
1. Shine a light source (light bulb) through the three different objects at this
station.
2. What happened to the light rays for each material?
LAB G: LIGHT INTERACTS WITH MATERIALS:
1. Shine a light source (light bulb) through the three different objects at
this station.
2. What happened to the light rays for each material?
3. Read page 191. Material in LAB E would be considered
________________________.
Material in LAB F would be considered _____________________________.
Material in LAB G would be considered _____________________________.
Complete the chart below based on your findings.
Type of
Material
Interaction with Light
Examples of
Material
Ray Diagram
TRANSPARENT
TRANSLUCENT
OPAQUE
Match the following examples of objects as to whether they are transparent,
translucent or opaque.
1.
2.
3.
4.
Desk _______________________
Leaf _____________________
Camera lens ___________________
Ice cube ______________________
_____________
5. Stained glass ________________
____________________________
6.
7.
8.
9.
Water _____________________
Mirror ____________________
Rainbow ______________________
Solid color shower curtain
10. Poster
LAB H: DESK DUTY: LUMINOUS vs. NON-LUMINOUS Read page 191
1. A pencil or other opaque objects are called ______
___________________________, meaning they ______ _____________ produce
_________________.
2. Where does the light come from in order for you to see an opaque object?
3. An object that produces its own light is considered
_______________________.
LAB I: LIGHT REFLECTION LAB: page 192
QUESTION: What type of material makes the best reflector?
HYPOTHESIS: I think
because
VARIABLES: manipulated: ___________________________________________
responding: _____________________________________________
2-controlled: __________________________________________________
MATERIALS & PROCEDURES: see page 192
OBSERVATIONS:
Material
Description
Transparent
Translucent,
or Opaque
Surface type
(smooth or
rough)
ANALYSIS: page 192
#6.
#7.
CONCLUSION TO LIGHT REFLECTION LAB:
Color
(shiny or
dull)
Qualitative
Measurement
Predict (good,
ave, poor)
Quantitative
Measurement
(mA)
Ranking
1st, 2nd,
etc..
APPLICATIONS:
LAB J: TYPES OF REFLECTION: Read page 193 to complete the chart below,
then
go to Station J to complete the second chart.
Type of
Reflection
Ray Diagram
Interaction with Light
type of surface: _______________
regular
bounce off in the _______
____________
reflected rays stay _______________ to
each other
image is ________________
type of surface:
_____________________
diffuse
each ray is reflected at a
____________
angle
the light is _________________
Classify each of the following objects (found at station J) as to whether they
would give a regular reflection or a diffuse reflection.
OBJECT: describe it
WHAT TYPE OF REFLECTION WOULD YOU
GET?
(diffuse or regular)
LAB K:: Read “Give it a Try” on page 194
1. When you wink your right eye, the ________________ eye in the mirror winks
back.
2. With 2 mirrors 90º to each other, when you wink your right eye the
____________
eye in the mirror winks back.
3. Any possible explanation for this?
GO#2: b) measure and describe angles of reflection
LAB L: 2.2: The Law of Reflection read page 194-196
1. The _________________ ray is the ray that goes into an object and bounces off
as a ________________ beam, giving regular reflection.
2. What type of surface gives the best reflections?
3. Examples of objects that allow you to see your image are: still _____________,
____________________, __________________, or even _____________
______________. The one that gives you the clearest reflection is a
_____________ (flat) __________.
QUESTION: What rule can you make that described how light reflects off a
flat mirror?
HYPOTHESIS:
VARIABLES: manipulated: ______________________________________
responding: _______________________________________
controlled: ________________________________________
MATERIAL AND PROCEDURE: SEE PAGE 195
OBSERVATION DRAWING
Top view of Mirror 
ANAYLYSIS QUESTIONS:
a. Label the diagram above using these words: incident ray, angle of
incidence, reflecting surface, normal, angle of reflection and reflected ray.
b. Using a protractor measure the angle of incidence= _______°
c. Using a protractor measure the angle of reflection= _______°
d. Explain how the angle of incidence and the angle of reflection compare.
Keep in mind instrumental errors.
CONCLUSION: The “LAW OF REFLECTION” states that….
ERRORS & CHANGES: