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Transcript
SNC2D1
OPTICS
UNIT D
CHAPTERS 10-12
1
LIGHT AND COLOUR
Additive Colour Theory & The Primary Colours (gizmo)
RGB are the primary colours of light. All other colours can be obtained by mixing
these colours at varying intensities. When RGB are mixed, white light is created.
When all colours of the visible spectrum are mixed, white light is created.
•
•
Perform gizmo & complete worksheet (see below)
Text ref. 387
Subtractive Colour Theory
1. Read pg. 388 then copy figure 10.20
2. What is a pigment?
3. What colour is absorbed by an object that is
a) cyan?
b) Magenta?
c) Blue?
d) Red?
When light is incident on an object, some of the component colours may be
absorbed, some may be reflected. The objects colour is determined by the
combination of all reflected colours.
F:\SNC2D1\Optics\1 What is Light\ColourTheories.pdf (EXTRA)
..\..\..\Optics\1 What is Light\AdditiveColorsgizmoWS.doc (OPTICS HANDOUT #1)
..\..\..\Optics\1 What is Light\AdditiveColorsgizmo_Key.doc
ANOTHER INTERACTIVE COLOUR PROGRAM:
http://www.exploratorium.edu/exhibits/mix_n_match/index.html
DBR6KRCKUR
2
OPTICS HANDOUT #2
THE NATURE OF LIGHT
What is Light and what makes one colour different from another?
DISPERSION - use page 386 to fill in blanks
Copy figure 10.6 on page 383
Text ref. 382-386
Text questions page 391 #1-5, 8-13
3
http://micro.magnet.fsu.edu/primer/java/wavebasics/index.html
- wave vs. colour simulator
F:\SNC2D1\Optics\Optics\xword_gr10_ch10_1.pdf (OPTICS HANDOUT #3)
EM ONLINE XWORD:
http://www.armoredpenguin.com/crossword/bin/crossword.cgi
EM PDF XWORD: EM XWORD.pdf (HANDOUT #4)
EM XWORDans.pdf
Other (EXTRA) wave theory files
F:\SNC2D1\Optics\1
F:\SNC2D1\Optics\1
F:\SNC2D1\Optics\1
F:\SNC2D1\Optics\1
What
What
What
What
Why is the sky blue?
http://science.howstuffworks.com/nature/climate-weather/atmospheric/sky.htm
What causes a rainbow?
is
is
is
is
Light\Characteristics of Waves.pdf
Light\Activity 3&4 Waves and Spectrum.pdf
Light\Electromagnetic Spectrum Comic.pdf
Light\Wave diagram.pdf
http://science.howstuffworks.com/question41.htm
Tour the spectrum:
http://www.pbs.org/wgbh/nova/gamma/spectrum.html
http://www.sciencesource2.ca/resources/flash_gr10_ch10_emr.swf
4
OPTICS HANDOUT #5
PRODUCING LIGHT
Light is a form of ________________ that can be detected by the human ______. It
travels or ________________ in all directions from the source.
Objects that __________________ light are called _______________. These can be
both ________________ and ________________. A ______________ object gives off
light as a result of either a _____________ or ____________ change. During the
change some other form of energy such as chemical or heat energy is converted to
light.
Most objects do not produce their own light. These are called _____________
sources of light. Light __________off of these objects.
Types of Light Production
Incandescence
A substance that gives off light because it is ______________________ is called
incandescent (ex. __________________________). Incandescent bulbs are very
inefficient, converting only _______ of the used electricity to light. The rest is converted
to __________.
Electric discharge
The process of producing light ____________________________________________
(ex. _________)
Luminescence
This is the emission of light by a material or an object __________________________.
Types of luminescence include:
Phosphorescence
- the process of producing light by the ____________ of _______ light resulting
in the emission of visible light over an ___________________ .
(ex._____________________)
Fluorescence
- the _____________ emission of visible light as a result of the ___________ of
___________ light.
Chemiluminescence
- the direct production of light as the result of a _________________ with little
or no ____ produced (ex. _____________)
5
Bioluminescence
- the production of light in living organisms as the result of a ______________
with little or no ____ produced (ex. _____________)
Triboluminescence
- the production of light from ________ as a result of crushing or colliding
certain crystals (ex.________________)
Fluorescent Light Bulbs
These utilize both __________________ and ______________to create light. The white
powder coating within the bulb ______________ to help make the light more ________.
Fluorescent bulbs are more efficient than incandescent converting ______ of the used
electricity to light.
LED (light emitting diode)
Light produced as a result of an ____________ flowing in a semiconductor (A
semiconductor is a material that allows an electric current to flow only in ___ direction.)
(ex. _______________)
LASER (Light Amplification by Stimulated Emission of Radiation)
Emits electromagnetic waves of exactly the same energy level, travelling in unisen in
exactly the same direction (ex. _______________)
PAGE REFERENCE: 394-398
TEXT QUESTIONS: PAGE 401 #2-7, 10, 15, 16
ADDITIONAL QUESTION (see page 398)
Which types of light production are involved in a plasma display (TV)?
6
DEMOS
LUMINOL– see Brad for recipe
CSI USE OF LUMINOL:
http://www.youtube.com/watch?v=iNl-I4DUSyI&feature=related
GAS DISCHARGE AND SPECTRUM VIEWERS
-
compare the light from an incandescent to that of a fluorescent
look at light produced from various pure substances
F:\SNC2D1\Optics\2 How is Light Produced\How is Light Produced (teacher).pdf
EXTRAS
F:\SNC2D1\Optics\1
F:\SNC2D1\Optics\2
F:\SNC2D1\Optics\2
F:\SNC2D1\Optics\2
What is Light\Ways of Producing Light.pdf
How is Light Produced\fluorescent bulb.pdf
How is Light Produced\Incandescent Light.pdf
How is Light Produced\led-diagram.jpg
7
OPTICS HANDOUT #6
RAY MODEL OF LIGHT
In the RAY MODEL OF LIGHT, light is represented as straight line arrows
which show the direction that light travels.
TEXT REFERENCE PAGES 404-406
Behavior of Light and it’s interaction with objects
Light can be…
 _______________ (light passes through the object)
 _______________ (light bounces off the object)
 __________________(light is absorbed and the energy is converted to heat)
What is the difference between regular and diffuse reflection? Use a diagram and
provide an example to help explain.(pg 406)
Transparent, Translucent and Opaque Substances
Objects can be classified according to how they transmit, reflect and absorb light.



transparent substances __________________________________________
(ex. __________)
translucent substances __________________________________________
(ex. ______________)
opaque substances ______________________________________________
(ex. ______)
The anatomy of a shadow
Using figure 10.47 on page 405 label the parts of the
shadow created by the moon.
Using the LCD projector create shadows and see if you
can observe the penumbra. What can you do to make
the penumbra more/less noticeable?
TEXT QUESTIONS PAGE 409 #4,5, 7,8,10, 13,18
CHAPTER 10 REVIEW Page 412 #2,4,6,8,10 – 17, 18, 19, 21 – 24, 26, 27
8
F:\SNC2D1\Optics\3 Properties of Light - Shadows\Properties of Light The Ray Model (teacher).pdf
F:\SNC2D1\Optics\3 Properties of Light - Shadows\Drawing Ray Diagrams-Shadows.pdf
F:\SNC2D1\Optics\3 Properties of Light - Shadows\Drawing Light Ray Diagrams (answers).pdf
F:\SNC2D1\Optics\3 Properties of Light - Shadows\lunar eclipse.jpg
EXTRAS
F:\SNC2D1\Optics\3 Properties of Light - Shadows\What is a Shadow (worksheets).pdf
9
PINHOLE IMAGES
As long as light remains within a particular medium it travels in a straight line until it is
absorbed or reflected by a surface. Because of this we see sharp shadows when a point
source produces light or when a light source is a large distance from the object. Ray
diagrams can be used to predict where light goes as it propagates through space.
Remember, rays are simply arrows that are drawn on paper to represent the direction of
propagation of light.
Pinhole images are those that can be formed on a screen when light from an object
passes through a tiny opening. Because the opening is small only one ray from each
point on the object can make it through. Of course this ray passes straight through. All
of the individual rays that pass through the aperture create an image that can be seen
with a screen. This image is almost like a bright shadow.
Images can be described by the following 4 characteristics;
1. Type
Real – if it can be focused on the screen.
Virtual – if it cannot be focused on a screen.
2. Attitude
Upright or inverted.
3. Size
Qualitatively – smaller, larger or same size as object.
Quantitatively – “magnification”
4. Position
Distance from the aperture (pinhole) to the image.
Ray diagrams can be used to predict where images will be found.
image
object
pinhole
screen
10
Investigating the Image Formed by a Pinhole Camera
Introduction:
One common type of pinhole camera consists of a box in two parts, one of which
can slide into the other. At one end of the camera is a small pinhole, at the other
end a translucent screen. In this activity you will determine the characteristics of
the image formed by such a pinhole camera, and explain how it is formed, using the
light ray model.
Materials:
black piece of paper with a small pinhole and a white piece of paper
light source (a candle or a capital ‘F’ on an overhead projector)
Procedure:
1. In a darkened room point the pinhole camera towards the lighted object. If
using the screens hold up the black paper and then the white paper screen
behind it. Observe the image formed on the screen.
2. Draw a diagram of the object and of the image as it appears on the screen.
Note the size and orientation of the image compared to the original object.
3. Observe what happens to the image on the screen when the object is moved
from right to left. Record your observations.
4. Without moving the position of the camera (or the black paper) move your
translucent screen (white paper) towards the pinhole while looking at the
screen. Observe and record what happens to the image.
5. From your same position as step 4 move your screen (white
paper) away from the pinhole while looking at the object. Observe and
record what happens to the image.
6. Without moving the translucent screen (white paper) move your camera
(black paper) towards the candle. Observe and record what happens.
7. Keeping the translucent screen (white paper) in the same position move your
camera (black paper) away from the candle. Observe and record what
happens.
Observations (5T)
PROCEDURE
1&2
OBSERVATION
11
3
4
5
6
7
Discussion
1. What two things can a photographer do to “zoom” in on a subject. Refer to procedure
#’s to help justify your answer. (2T)
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
2. a) Where does the light from the top of the object appear on the image formed on
the pinhole camera screen? (1T)
_______________________________________________________________________
b) From this observation, what can you infer about the path of the light as it travels
from the object through the pinhole to the screen of the camera? (1T)
_______________________________________________________________________
3. Draw a light ray diagram from a side view to show where the light from the top and
bottom of the object strikes the screen. Sketch the rest of the image. (2T)
4. a)What are the following characteristics of the image formed by a pinhole camera?
(2T)
Attitude: _______________________________________________________
Type:
_______________________________________________________
b) Under what situation is the image larger than the object? (2T)
5. If you could produce an image of yourself using a pinhole camera and you waved
your left hand, which hand in the image would wave back? The hand on the left or
right side of the screen? Try to justify your answer. (2T)
12
..\..\..\Optics\4
..\..\..\Optics\4
..\..\..\Optics\4
..\..\..\Optics\4
..\..\..\Optics\4
..\..\..\Optics\4
Pinhole
Pinhole
Pinhole
Pinhole
Pinhole
Pinhole
images\Pinhole Camera Diagrams.pdf
images\Pinhole Camera Lab Observation chart.pdf
images\Pinhole Camera Lab.pdf
images\Pinhole Cameras (student).pdf
images\Pinhole Cameras (teacher).pdf
images\Ray Diagrams For Pinhole Cameras.pdf
CHAPTER 10 QUIZ
13
Reflection of Light
Regular Reflection
Regular reflection occurs when light is reflected off a _smooth
______ surface.
Since light travels in straight lines, the angle at which the light strikes the surface (the
_angle of incidence___) is the same as the angle at which the light
leaves the surface at (the _angle of reflection_)
Laws of Reflection
1. The angle of reflection always __=_ the angle of incidence.
2. The incident ray, reflected ray and normal all lie in the _plane__
Reflection worksheet
Mirror image worksheet
14
Optics Experiment #2: Plane Mirrors
Purpose
To discover the Laws of Reflection and to locate images created by a plane mirror.
Materials
Plane mirror
White paper
Ruler
Protractor
Procedure
1.
2.
3.
4.
Divide a blank sheet of paper in half by drawing a line across the page.
On one side sketch a simple object.
Place the mirror on the line with the reflective side facing the object.
Shine light incident from one end of your object onto the mirror at 4 different
points of incidents. Draw each incident and reflected ray.
5. Repeat #4 with the opposite end of your object.
6. Remove the mirror and extend all reflected rays backwards (behind the mirror)
using dotted lines.
Analysis
1. What do you notice about the extended rays? (1)
2. Sketch the image of your object onto your observation page.
3. Draw a line from each of your object points to their corresponding image points.
a) Measure the angle these lines make with the mirror.
b) Measure the object and image distances.
c) What can you say about the image position? (2)
4. What are the characteristics of your image? (2)
Thinking & Investigation
Use of processing skills and
strategies (e.g., performing
L2
uses processing
skills and
strategies with
limited
effectiveness
L3
uses processing
skills and
strategies with
some
effectiveness
L4
uses processing
skills and
strategies with
considerable
effectiveness
L5
uses processing
skills and
strategies with a
high degree of
effectiveness
Specific Criteria
Procedure & analysis
carried out with precision
and attention to detail.
Actively participated in the
lab activity in a safe
manner
/5
Use of critical/creative
thinking processes, skills and
strategies (e.g., analysing,
uses critical/
creative thinking
processes, skills,
and strategies
with limited
effectiveness
uses critical/
creative thinking
processes, skills,
and strategies
with some
effectiveness
uses critical/
creative thinking
processes, skills,
and strategies
with considerable
effectiveness
uses critical/
creative thinking
processes, skills,
and strategies
with a high
degree of
effectiveness
Analysis questions 1,3c
and 4 answered
thoughtfully with
justification where
appropriate.
and recording, gathering
evidence and data,
observing,manipulating
materials and using
equipment safely)
interpreting, forming
and justifying conclusions on
the basis of evidence )
/5
Extension
Try quick lab on page 417
15
Curved Mirrors
- a _convex mirror__bulges out (like the outside of a spoon)
- a _concave mirror____ bulges in (line the inside of a spoon)
vertex (V) the __________________________
centre of curvature (C) if the mirror were extended to be a
__________, this point would be the _________
principal axis (PA) line that joins the _____ and the __________________________
_______________________________________________________________________
Consider the following diagram of a concave mirror;
Focal length
Incident rays(parallel to PA)
Reflected rays
Focal point
The focal point is _the common point on the principle axis through which all
_rays initially parallel to the PA will pass after reflection_________________.
It is found __half way_______ between the C and V.
16
Consider the following diagram of a convex mirror;
A convex mirror is also sometimes called a diverging mirror. Why? _________________
_______________________________________________________________________
Why do you think the focal point is “virtual”? ___________________________________
_______________________________________________________________________
_______________________________________________________________________
Locating Images
Like plane mirrors, images are always found where the _reflected________ rays
originating from the same point on an object __intersect_______.
Summarize the rules for drawing ray diagrams for curved mirrors from page 422 & 426.
Use the diagram to illustrate these rules.
Concave Mirror
Ray 1: _______________
_____________________
_____________________
Ray 2: _______________
_____________________
_____________________
Convex Mirror
Ray 1: _______________
_____________________
_____________________
Ray 2: _______________
_____________________
_____________________
17
Page 427 #3-5; page 433 #15
Image Magnification
M
hi
ho
Page 424 #1-3 (top)
Page 425 #1-3 (top)
Page 424,5 #1-3 (btm) – preferably after lab #3
Challenge: Where would you have to put a 2.5 cm high object in order to create an
image that is 10 cm tall and 20 cm from the mirror?
Algebra Review: Rearranging equations
1. Rearrange the formula so that it solves for x;
xy  z
2. Rearrange the formula so that it solves for d;
ab  cd
3. Rearrange the following formula so that it solves for…





a) 
b) 
4. Rearrange the two magnification equations into their 3 different forms.
18
OPTICS LAB #3: CONCAVE MIRROR ACTIVITY
1. Determine the focal length of your mirror as per teacher instructions.
f = ____________
2. Complete the following chart through experimental observations
do
2.5f
2f
1.5f
1f
0.5f
di
ho
hi
Type
attitude
di/do
hi/ho
NO IMAGE
VIRTUAL IMAGE – LOOK INTO MIRROR TO SEE IT!
3. Draw detailed scale ray diagrams for each of your object positions. Make
measurements on your diagram to complete the following table. Each group
member is responsible for at least one.
Scale distances
do
di
2.5f
2f
1.5f
1f
0.5f
scale
Actual distances
do
di
2.5f
2f
1.5f
1f
0.5f
ho
ho
hi
hi
Type
attitude
di/do hi/ho
4. How do your image positions compare between the first and third chart? (1)
Poor
satisfactory
good
excellent
19
5. Why are they not exactly the same? (i.e.What are the sources of error?)(2)
______________________________________________________________
____________________________________________________
6. Why is there no image when do=1f? (1)
_________________________________________________________
7. Why is a virtual image produced when do=0.5f? (1)
_________________________________________________________
8. hi/ho is how magnification is calculated. How else can it be calculated?
Justify your answer.(2)
______________________________________________________________
____________________________________________________
Thinking & Investigation
Use of processing skills
and strategies (e.g.,
performing and
recording, gathering
evidence and data,
observing,manipulating
materials and using
equipment safely)
Use of critical/creative
thinking processes, skills
and strategies (e.g.,
analysing,
interpreting, forming
and justifying
conclusions on
the basis of evidence )
Communication
Expression and
organization of ideas
and information (e.g.,
clear expression, logical
organization) in oral,
visual, and/or written
forms (e.g., diagrams,
models)
L1
uses
processing
skills and
strategies with
limited
effectiveness
L2
uses
processing
skills and
strategies with
some
effectiveness
L3
uses
processing
skills and
strategies with
considerable
effectiveness
L4
uses processing
skills and
strategies with a
high degree of
effectiveness
Specific Criteria
Procedure & analysis
carried out with precision
and attention to detail.
Actively participated in the
lab activity in a safe
manner
(weighting: 2 marks)
uses critical/
creative
thinking
processes,
skills,
and strategies
with limited
effectiveness
uses critical/
creative
thinking
processes,
skills,
and strategies
with some
effectiveness
uses critical/
creative
thinking
processes,
skills, and
strategies
with
considerable
effectiveness
uses critical/
creative thinking
processes,
skills,
and strategies
with a high
degree of
effectiveness
Type and Attitude identified
correctly for each object
position.
(weighting: 1 marks)
expresses and
organizes ideas
and information
with limited
effectiveness
expresses and
organizes ideas
and information
with some
effectiveness
expresses and
organizes ideas
and information
with
considerable
effectiveness
expresses and
organizes ideas
and information
with a high
degree of
effectiveness
Ray diagrams completed
correctly with precision
(weighting: 5 marks)
Questions 4-8 answered
thoughfully and supported
by evidence.
(weighting: 7 marks)
20
Refraction of Light
Refraction is the bending of light as it travels from one medium into another medium. It
is responsible for many optical phenomena including the formation of mirages,
dispersion and production of images from lenses. picture
Partial Reflection
Incident ray
The refracted ray bends towards the normal when light travels from a medium in which
the speed of light is fast to a medium in which the speed of light is slow. (θR<θi)
If a light ray travels from a medium in which its speed is slower to a medium in which its
speed is faster the refracted ray bends away from the normal. (θR>θi)
Light is fastest in a vacuum, travelling 3.0 x 108 m/s. symbolically this number is “c”
Index of Refraction, n
A number that communicates how much slower light is in a particular medium compared
to c.
c
n
v
A material with a large index of refraction is said to be “optically
dense”.
See table 11.5 on page 437 for a list of common n values.
Page 438# 1-3 (top) and #1-3 (btm)
21
Dispersion
Have a look at figure 11.37 on page 440 and come up with a simple explanation for why
white light separates into it’s colours upon entering a new medium at an angle.
Apparent Depth
Reproduce figure 11.31 on page 436 and explain the role of refraction in the creation of
the image of the chest.
Try quick lab D17 on page 435.
Mirages
Read “A wall of water” on page 497. Have a look at figure 11.41 on page 443. Why does
the road look wet?
http://finland.fi/public/default.aspx?contentid=160069&contentlan=2&culture=en-US
22
http://www.islandnet.com/~see/weather/elements/mirage1.htm
Did you know?
Because of refraction the amount of daylight we receive is extended.
23
SNELL’S LAW
The mathematical relationship between the incident angle (θi) and the refracted angle
(θR).
Medium 1
Medium 2
sin 1
 cons tan t
sin  2
n1 
c
v1
n2 
c
v2
cons tan t 
n2
n1
sin 1 n2

sin  2 n1
OR
n1 sin 1  n2 sin 2
Rearrange this equation to solve for each variable.
Page 441 #1-3, page 442 #1-3
24
Optics Experiment #4: Refraction
Introduction/Purpose
In this experiment, you will make measurements and perform calculations in an attempt
to determine the index of refraction of a material.
Materials



Ray box with single slit card
½ circle glass prism (or rectangle)
Ruler, paper, protractor
Procedure
1.
2.
3.
4.
5.
6.
7.
8.
On a plain piece of paper, trace the glass block.
Remove the block and mark the midpoint of the flat side.
Draw in the normal (air will be the incident medium)
Draw incident rays at angles of incidence; 10, 20, 30, 40 and 50 deg.
Replace the block and shine a ray at each incident angle from #4.
Mark where the light ray emerges from the glass block.
Remove the block and draw in the refracted rays using a ruler.
Measure the angles of refraction.
Observations


Draw a table with the following headings: Angle of Incidence(θi), Angle of
Refraction(θR), sinθi, sinθR, ni, nR
Include the paper on which you traced the light rays.
Analysis
1. As the angle of incidence increases, what happens to the angle of refraction? (1)
_______________________________________________________________________
_______________________________________________________________________
2. How do the angles of refraction compare with the angles of incidence? In which
direction does the light bend?(1)
_______________________________________________________________________
_______________________________________________________________________
3. What happens to the speed of light as it enters the glass? Explain your
answer.(2)
_______________________________________________________________________
_______________________________________________________________________
25
4. For each ray, calculate the index of refraction for the glass knowing that the
index of refraction for air is 1.0003. Add your answers to your table. Show one
detailed calculation below.(3)
5. Calculate the average index of refraction for the glass. (1)
6. Calculate the speed of light in the glass. (2)
Thinking & Investigation
Use of processing skills
and strategies (e.g.,
performing and recording,
gathering
evidence and data,
observing,manipulating
materials and using
equipment safely)
Use of critical/creative
thinking processes, skills
and strategies (e.g.,
analysing,
interpreting, forming
and justifying conclusions
on
the basis of evidence )
Communication
Expression and
organization of ideas
and information (e.g., clear
expression, logical
organization) in oral, visual,
and/or written forms (e.g.,
diagrams, models)
L1
uses
processing
skills and
strategies with
limited
effectiveness
L2
uses
processing
skills and
strategies with
some
effectiveness
L3
uses
processing
skills and
strategies with
considerable
effectiveness
L4
uses
processing
skills and
strategies with
a
high degree of
effectiveness
Specific Criteria
Procedure & analysis
carried out with precision
and attention to detail.
Actively participated in the
lab activity in a safe manner
(weighting: 2 marks)
uses critical/
creative
thinking
processes,
skills,
and strategies
with limited
effectiveness
uses critical/
creative
thinking
processes,
skills,
and strategies
with some
effectiveness
uses critical/
creative
thinking
processes,
skills, and
strategies
with
considerable
effectiveness
uses critical/
creative
thinking
processes,
skills,
and strategies
with a high
degree of
effectiveness
Analysis questions
answered thoughtfully and
supported by evidence.
(weighting: 10 marks)
expresses and
organizes ideas
and information
with limited
effectiveness
expresses and
organizes ideas
and information
with some
effectiveness
expresses and
organizes ideas
and information
with
considerable
effectiveness
expresses and
organizes ideas
and information
with a high
degree of
effectiveness
Calculations shown with
detail by including
- given information
- equations used
- Equation rearranging
- units where needed
(weighting 5 marks)
26
Lenses
Lens - is a transparent object with at least one curved side that causes
light to refract.
Converging Lenses (convex): A lens that brings parallel light rays towards a
common point.
Diverging Lenses (concave): A lens that spreads parallel light rays away from a
common point.
* Copy figure 11.50 from page 450.
* Learn the rules for drawing ray diagrams (locating images) for these lenses
(page 452 and page 453)
Ray diagram worksheet for lenses
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Thin Lens Equation
Allows one to mathematically predict where an image will be formed or
where to place an object to get an image at a desired location.
1
1
1
 
f di do
Notes:
 di must be negative for virtual images.
 f must be negative for diverging lenses.
 If di and do are known, magnification can be calculated.
Task:
1. Calculate di for each of your ray diagrams from Friday.
2. Measure di for each of your ray diagrams and compare.
Text Questions: page 455 #1-3; page 456 #1-3; page 457 #1-3
_______________________________________________________________________
Chapter 11 Quiz Topics
Ray diagrams and image characteristics for images created by
 Plane mirrors
 Curved mirrors
 Lenses
Magnification calculations
Refraction
 Index
 Snell’s law
 Dispersion, mirage formation, apparent depth
Thin Lens equation
Some chapter review: page 464 #2,7,10, 11 – 15, 20;
http://www.sciencesource2.ca/resources/matchquiz_gr10_ch11a/index.html
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THE HUMAN EYE
1) Label the diagram of the cross section of the eye using page 470.
2) What is the purpose of the iris? Under what conditions would your pupils
dilate?
3) How is the focal length of the lens adjusted? This process is called
accommodation? Why is this necessary?
4) As people age their eyesight often deteriorates because their ability to
accommodate decreases. Reading glasses are often needed to help focus on
images up close.
5) Draw a ray diagram that shows how an object is seen by a normal eye.
6) Draw similar diagrams that show what it means to be farsighted and
nearsighted.
a) What object distances are a problem for each of these conditions?
b) What are the possible causes and solutions to each of these conditions?
7) What is astigmatism? What happens during laser surgery to correct this
problem?
8) There are two types of cells called photoreceptors that make up the retina.
What are they? What is the purpose of each?
9) Can you find your blind spot? See page 472
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The Cow Eye Dissection
http://www.exploratorium.edu/learning_studio/cow_eye/
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