high school part 2 /2 by ssl technologies physics ex-49 click the mirror equation is a geometrical...
TRANSCRIPT
High School
Part 2 /2
by SSL Technologies
Physics Ex-49
Click
The mirror equation is a geometrical derivation for solvingproblems with curved mirrors.
Where: f = focal length (in metres) do = Object distance (in metres)
di = Image distance (in metres)
Where: M = magnification factor (no units) hi = height of image (in metres) ho = height of object (in metres)
and
PART-2 /2
Physics Ex-49
Click
Be sure to observe the following sign conventions when usingthe mirror formula:
All distances are measured from the vertex of a curved mirror. Distances of objects and real images are positive. Distances of virtual images are negative. Object and image heights are positive when upright and
negative when inverted.
Parabolic mirrors are used as reflectors for searchlights, flashlights,projectors and automobile headlights.
Where: f = focal length (in metres) do = Object distance (in metres)
di = Image distance (in metres)
PART-2
Physics Ex-49
Click
When M is less than 1,the image is reduced.
When M is negative,the image is inverted.
Physics Ex-49
Type (real or virtual): _______________
Location: _______________
Magnification: _______________
Attitude (upright/inverted): _______________
Question-1
An object is 60 cm from a converging mirror whose radius ofcurvature is 30 cm.
Determine the characteristics of the image.
Click
Real
Click
20 cm (in front of mirror)
- 0.33 (inverted and smaller than object)
Inverted
Physics Ex-49
Type (real or virtual): _______________
Location: _______________
Magnification: _______________
Attitude (upright/inverted): _______________
Question-2
An object is 25 cm from a concave mirror whose focal lengthis 15 cm. Determine the characteristics of the image.
Click
Real
Click
37.5 cm (in front of mirror)
- 1.5 (inverted and larger than object)
Inverted
Physics Ex-49
Type (real or virtual): _______________
Location: _______________
Magnification: _______________
Attitude (upright/inverted): _______________
Question-3
An object is placed 7.5 cm from a concave mirror that has a focallength of 15 cm. Determine the characteristics of the image.
Click
Virtual
Click
15 cm (behind mirror)
2 (upright and larger than object)
Upright
Negative sign indicates virtual image
Physics Ex-49Question-4
A converging mirror has a focal length of 15 cm. Where wouldyou place an object in front of this mirror in order to producean upright, virtual image, twice as tall as the object?
ClickClickNegative sign indicates
virtual image
Physics Ex-49
This means a virtual image (di is negative).
Question-5
What is the focal length of a concave mirror when an object thatis placed 2 cm in front of the mirror produces an image that isseen 5 cm behind the mirror?
ClickClick
Physics Ex-49Question-6
A concave mirror has a focal length of 30 cm. A square object,4 cm per edge, is situated with its center 10 cm in front of themirror. Determine:
ClickClick
a) The position (center) of the image.
Physics Ex-49Question-6
A concave mirror has a focal length of 30 cm. A square object,4 cm per edge, is situated with its center 10 cm in front of themirror. Determine:
ClickClick
b) The area of the image.
Physics Ex-49Question-7
Illustrated below is an object situated in front of a convex mirror.Graphically, find the image and state its characteristics. .
ClickClick
The image is virtual, upright, reduced and located behind the mirror.
NOTEConvex mirrors always produceimages that are virtual, upright
and reduced.
Physics Ex-49Question-8
An object is placed 10 cm in front of a convex mirror whosefocal length is 15 cm.
Determine the characteristics of the image.
Click
The image is virtual (since di is negative), upright (since M is positive),smaller than the object (since M = 0.6) and located behind themirror. Click
d i
Physics Ex-49Question-9
When an object is 30 cm in front of a concave mirror, its imageis real and situated 15 cm from the mirror.
Determine the location of the image when the object is placed 6.0 cm from the mirror.
ClickClick
The image is virtual and located behind mirror.
Physics Ex-49Question-10
Fill in the four (4) missing quantities in the table below:
ClickClick
MIRRORTYPE
FOCALLENGTH
OBJECTDISTANCE
IMAGEDISTANCE
OBJECTHEIGHT
IMAGEHEIGHT
Concave 4 cm -12 cm 2 cm
Convex 10 cm -7 cm 1 cm
3 cm 8 cm
-23.3 cm 0.7 cm
1 2
3 4
Physics Ex-49Question-11
An object is placed in front of a convex mirror as illustrated below.
Draw and label the light rays necessary to locate the image.
Incident ray
Reflected ray
Extended ray
Incident ray
Reflected ray
Extended ray
Image
Click
Image is virtual, upright and reduced.
Physics Ex-49
A) 10.0 cm
B) 20.0 cm
C) 60.0 cm
D) 90.0 cm
E) 120.0 cm
Question-12
An object 45.0 cm high is placed in front of a convex mirror whosefocal length is 30.0 cm.
If a virtual image 15.0 cm high is formed, determine the distancethe object is from the mirror.
Click
Step-2 Calculate do
GivenStep-1 Calculate di
REMINDER
Convex mirrors have a negative focal length.
Virtual images have a negative distance.
SSLTechnologies.com/science