Physics 20 Lab - Reflection from a Plane Mirror
Part 1: Single Mirror
Purpose: To determine the position of an image in a plane mirror using a laser or ray
box. To show that the laws of reflection apply.
Materials:
Apparatus:
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1 Object
plane mirror
work sheet
Ray box or laser
Pencil
Sticky tape
Protractor
Procedure :
1. Draw a dot on a piece of paper to represent the object.
2. Hold a mirror vertically on the paper and draw a line at the back of the mirror.
3. Position the ray box or laser to the right side of the object and point the light at the
image in the mirror. (Like on the diagram)
3. With your pencil, trace the light ray up to the mirror.
4. Position the ray box or laser to the left side of the object and point the light at the
image in the mirror
5. With your pencil, trace the light ray up to the mirror.
7. Remove the mirror.
8. Extend the two established lines of sight behind the mirror to locate the position of
the image where the 2 lines cross. Label this point image.
9. Measure the distance from the object to where the mirror was.
Object Distance = _____________________
10. Measure the distance from the image to where the mirror was.
Image Distance = ______________________
Analysis: To be completed on the looseleaf.
1. Are the object distance and image distance the same? Why?
2. Draw an eye on the worksheet and show the path of the light rays going from the
object to the eye.
3. Complete the ray diagram by drawing the normal and labeling the angle of incidence,
angle of reflection for the light ray going from the object to the eye.
Conclusion:
1. What relationship exists between the angle of incidence and the angle of reflection?
2. Where is the image located with respect to the position of the object? Measure the
distances and compare.
3. What could have caused you to have errors in your experiment?