Download MIRRORS reflect light and obey the law

Physics - Chapter 18
Mirrors and Lenses
Name___________________
Optics – Reflection:
Definition:
Law of Reflection:
MIRRORS reflect light and obey the law _____________________________________
There are three types of mirrors.
Plane Mirror
Concave Mirror
Convex Mirror
Optics - Ray Tracing
Definition:
How can wave be a ray?
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
Optics – Plane Mirrors – Flat Surface
Law of Reflection:
Draw a ray diagram and label all parts.
Name the Optical Image:
Nature:
Orientation:
Size:
Plane Mirrors – Flat Surface
Draw a diagram of a Plane Mirror. Name the IMAGE.
Practice Problem: Two plane mirrors are at right angles to each other as shown. If a pin is placed on the
shiny side of each, how many images are formed? Hint: Images can form images, too.
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
Optics – Spherical Mirrors
Two Types:
Optics – SPHERICAL CONCAVE MIRROR
Draw a ray diagram of the concave mirror. Describe the characteristics.
Optics – SPHERICAL CONVEX MIRROR
Draw a ray diagram of the convex mirror. Describe the characteristics.
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
MIRROR PROPERTIES
When rays reflect from a mirror and ______________________________, they pass through the image.
The image can be seen on a __________________________ or a piece of paper. This image is called a
_________________ ___________________.
If the rays are coming from __________________________ source, they are striking the mirror as
________________________________. They will reflect, converging at the
____________________________________________, forming an IMAGE.
When the rays reflect from a mirror and _______________________ from a point ________________ the
mirror, the image is ________________________ which means the image cannot be pictured or
projected on a screen.
MIRROR EQUATION
The equation that shows a relationship between the focal length (f), distance to object (do), and distance to
image (di) can be written:
For a concave mirror, the focal length is __________________________.
For a convex mirror the focal length is ____________________________.
If the image is real, in front of the mirror, the distance to image is __________________________.
If the image is virtual, behind the mirror, the distance to image is __________________________.
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
MAGNIFICATION EQUATION
The relationship of image size compared to object size represents magnification. Also the relationship
between the negative of the image distance compared to the object distance represents magnification.
These relationships can be written as:
When the image size is ________________________, the image is upright (virtual).
When the image size is ______________________, the image is inverted (real)
Practice Problem: An object 2.0 cm high is 30.0 cm from a concave mirror. The radius of curvature of
the mirror is 20.0 cm.
What is the location of the image?
What is the size of the image?
Practice Problem: Find the location of the image in a concave mirror if the object is 2.0 cm in height and
is 5.0 cm from the mirror with a focal length of 10.0 cm. How large is the image?
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
MIRROR PROPERTIES – The Focus of a Spherical Concave Mirror
Draw a ray diagram
When parallel rays of a concave (spherical) mirror ______________________ so that they
__________________________converge at the focal point, the image appears as a
________________________ or ___________________________, not a point creating the effect of
________________________ ______________________________.
To prevent the effect, the mirror is constructed to be ____________________________, causing all the
rays to ____________________ through one point, the ______________
____________________________.
Examples of parabolic mirrors that behave in this manner are:
__________________________________, _________________________________
___________________________________, and_________________________________
Ray Tracing of the Spherical Concave Mirror - Three types of principal rays:
p-ray:
f-ray:
c-ray:
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
Optics – Spherical Concave Mirror – Ray Tracings to locate image
Object > Center of Curvature (2F)
Object = Center of Curvature (2F)
Object between Center of Curvature (2F) and Focus (F)
Object = Focus (F)
Object < Focal Length (f)
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
Practice Problem:
a) Construct 2 ray diagrams to illustrate what happens to the size of the image as an object is brought
nearer to a spherical concave mirror when the object is outside the focus.
b) Construct 2 ray diagrams to illustrate what happens to the size of the image as an object is brought
nearer to a spherical concave mirror when the object is inside the focus.
Practice Problem: A spherical concave mirror, focal length 20 cm, has a 5 cm high object placed 30 cm
from the mirror.
Draw a ray diagram, construct the image and name the image.
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
Optics – Spherical Convex Mirror
Construct the image for an object located outside a spherical convex mirror and name the image.
Practice Problem: Construct 2 ray diagrams to illustrate what happens to the size of the image as an
object is brought nearer to a spherical convex mirror.
Practice Problem: A spherical convex mirror, focal length 15 cm, has a 4 cm high object placed 10 cm
from it.
a) Draw a ray diagram, construct the image and name the image.
b) Use the mirror equation to calculate:
i.
The position of the image
ii.
The magnification
iii.
The size of the image
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Physics - Chapter 18
Mirrors and Lenses
Name___________________
Optics – Sign Conventions for Mirrors
Focal Length:
Magnification:
Image Distance:
CONCAVE MIRRORS produce REAL IMAGES when the
VIRTUAL IMAGES are produced by:
object is:
_________________________________________________
__________________________________
_________________________________________________
__________________________________
_________________________________________________
__________________________________
_________________________________________________
Optics – Concave vs. Convex Mirrors
Concave
Convex
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