Objectives: To formulate ideas about how reflected light travels to your eyes.

Materials: paper, cardboard, two mirrors, 5 stick pins, 1 piece of tape

Methods:

Part I
1. Tape a piece of binder paper on a piece of cardboard. Place a mirror half-way up the long direction on the piece of paper. Draw a line on the paper to indicate the location of the back of the mirror. This is the reflecting line.

2. Stick a pin into the paper about 3 to 5 cm from the mirror and in line with the center of the mirror. This is the object pin show in the diagram.

3. Now close one eye and look at the image of the pin in the mirror. Stick two additional pins (sighting pins) into the paper formed a line of sight. The two sighting pins and the image should all line up. Your eye should be at arm's length from the pins as you stick them in place so that all three pins will be in clear focus simultaneously.

4. Move your head to the other side of the object pin and again stick two additional pins so as to form a line of sight.

5. Remove the pins and mark their locate on the paper. Label the object pin OP. Remove the mirror and make sure that the line showing the location of the mirror is drawn completely across.

6. Draw a line connecting the first two sighting pin locations and extend it behind the mirror location. Repeat with the second two sighting pins.

Part I  Analysis Questions.
Q1. Where do the lines of sight converge?

Q2. Measure the distance from the object pin to the mirror surface. This is the object distance. What is this distance?

Q3. Measure the distance from the mirror to where the lines of sight converge. This is the image distance. What is this distance.

Q4. Compare the object distance to the image distance.

Q5. Where is the image of an object in a plane mirror located? (Include this in the conclusion.)

PART II.

Methods
1. Hinge two mirrors together with transparent tape to allow them to open at various angles. Use clay and a protractor to hold the two mirrors at an angle of 72°. Place an object to be observed inside the angled mirrors. Count the number of images resulting from this system and record in a data table.

2. Reduce the angle of the mirrors by 5° at a time and count the number of images at each angle. Record your findings in the data table.

Part II Analysis Questions.
Q5. Explain the reason for the multiple images you have observed. (Hint: keep it simple.)

Q6. What effect does the angle between the mirrors have on the number of images?

PART III.

Methods
1. Using a similar procedure to Part I, determine the location of an image in a convex and concave mirror.

Part III. Analysis Questions.
Q7. How do the images in the three types of mirrors differ?

Q8. What are some uses of all three trypes of mirrors?