PhysicsLAB Lab
Ray Diagrams for Converging Mirrors

In this lab, you will construct the SIX special ray diagrams for a converging, or concave, mirror. In each diagram, use an arrow, 1.0 cm tall, pointing upwards as the object. Label it with an O. For your convenience, blank diagrams will objects already provided are located on this page -- in IE use landscape mode with margins of 0.5. Each case will use the three rays outlined in the lesson on spherical mirrors where you are provided with diagrams showing you how each image is formed. Keep your three rays color-coded - that is, let ray #1 be the same color in each diagram, similarly with ray #2 and ray #3. When all three rays come together they locate your image. Draw the image in and label it with a capital I. You are then to measure, in centimeters, do, di, O and I to the nearest 10th of a centimeter.
 
Examples of each ray are shown below.
 
Remember that
  • do represents the distance from the object to the mirror when measured along the axis of the mirror.
  • di represents the distance from the image to the mirror when measured along the axis of the mirror.
  • O is the height of the object (measured from tip to base - this should be close to 1.0 cm)
  • I is the height of the image (measured from tip to base)
 
The magnification of a mirror is equivalently defined as either of the following ratios: M = | I/O | or M = | di/do |. You will be using them to evaluate the precision of your diagrams.
 
Your diagrams will be graded on neatness, so be careful. Remember your arrows!
 
 
Case I: the object is located infinitely far away
 
Refer to the following information for the next five questions.

The image is formed on the line between region ____ and ____.
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
The purpose of this construction is to locate the ____ which defines the focal length of the mirror.
 

 
 
Case II: the object is located in Region I
 
Refer to the following information for the next four questions.

The image is formed in region ____.
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Using the results of your diagram, measure each of the following four distances. Then calculate each magnification and the percent difference between their values.

measurements (cm)
O =
do =
di =
I =

magnification comparisons
M = |di/do|
M = |I/O|
% difference =
 
 
Case III: the object is located at the center of the mirror
 
Refer to the following information for the next four questions.

The image is formed on the line between region ____ and ____.
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Using the results of your diagram, measure each of the following four distances. Then calculate each magnification and the percent difference between their values.

measurements (cm)
O =
do =
di =
I =

magnification comparisons
M = |di/do|
M = |I/O|
% difference =
 
 
Case IV: the object is located in Region II
 
Refer to the following information for the next four questions.

The image is formed in region ____.
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Using the results of your diagram, measure each of the following four distances. Then calculate each magnification and the percent difference between their values.

measurements (cm)
O =
do =
di =
I =

magnification comparisons
M = |di/do|
M = |I/O|
% difference =
 
 
Case V: the object is located at the focus of the mirror
 
Refer to the following information for the next two questions.

Choose the correct property. This image is
 
because
 
 
 
Case VI: the object is located in Region III
 
Refer to the following information for the next four questions.

The image can be formed in region ____, region ____, or region ____.
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Choose the correct property. This image is
 
Using the results of your diagram, measure each of the following four distances. Then calculate each magnification and the percent difference between their values.

measurements (cm)
O =
do =
di =
I =

magnification comparisons
M = |di/do|
M = |I/O|
% difference =

Teacher Certification: 



This form is to be completed individually at the completion of your lab. Input only your numerical values - the correct units have already been supplied on the form. Make sure that your teacher or his/her designee signs off the Teacher Certification area before posting your final submission.


PhysicsLAB
Copyright © 1997-2025
Catharine H. Colwell
All rights reserved.
Application Programmer
    Mark Acton