1. Seeing Things Image Location in Plane Mirrors

2. Seeing Things Image Location in Plane Mirrors

3. We see the Object when looking directly at it, because rays of light go from it straight into our eyes.

4. Experience has trained our Eye-Brain that things are located in the direction the light comes from.
Rectilinear Propagation is the term for this

5. When we look in the Mirror we see an Image of the Object.

6. Experience has trained our Eye-Brain that things are located in the direction the light comes from.
Rectilinear Propagation is the term for this

7. Rays of light must be coming straight from the what we see in the mirror (the Image) into our eyes. That is the way we see things.

8. The Image appears to be behind the Mirror
The Image appears to be behind the Mirror. But the light rays can not come through the Mirror. Mirrors are Opaque.

9. Two Questions
Where does the Image appear to be located?

10. Two Questions
How can the light rays appear to go through an opaque Mirror?

11. Question 1) Where does the Image appear to be located in a Plane Mirror? Image Location Lab

12. Image Location Lab
Place an Object in front of the MIRA on a sheet of scrap paper.
Notice you can see a reflection of the Object in the MIRA. If you use an Object/Image Stick you even see the word Image in the reflection.
#1 scrap paper not scrape

13. Place an Image locator (a second Object/Image Stick) behind the MIRA.
You can see the Image locator through the MIRA. If you use an Object/Image Stick, turn it around so that you can see the word Image through the MIRA

14. Move the Image locator until it appears to overlap the Image.

15. Trace the location of the Object.

16. Trace the location of the Mirror.

17. Trace the location of the Image (Image locator).

18. Move the Object twice (2X’s) more
Trace all Object and the Image locations
Be careful to keep the MIRA in the same place.

19. You should have a piece of paper that looks similar to
Draw a line from the centre of the Object to the centre of the Image so you have have a piece of paper that looks similar to O1 O2 O3 I1 I3 I2
What are two observations that can be used to predict the position of the Image in a mirror?
Try the Bulls Eye activity
Stop Slide show here. Allow students to answer question 14)

20. Do the Image Location Lab
Your Turn
Do the Image Location Lab
Stop Slide show here. Allow students to answer question 14)

21. Image Location Lab Answers Follow
Stop Slide show here. Allow students to answer question 14)

22. The line connecting the Object and Image intersects the Mirror at 90 °
What are two observations that can be used to predict the position of the Image in a mirror?
The distance from the Object to the Mirror (dO). is the same as the distance from the Image to the Mirror (dI). Or dO=dI.
The line connecting the Object and Image intersects the Mirror at 90 °

23. Use your observations to show where, and then describe how, you would place a MIRA or Reflect-View so that the tip of the arrow always appears to hit the Bulls Eye
Draw a line connecting the Arrow Tip and the Bulls Eye (Object & Image)

24. Place the Mirror in the middle of the line dO=dI
Use your observations to show where, and then describe how, you would place a MIRA or Reflect-View so that the tip of the arrow always appears to hit the Bulls Eye
Place the Mirror in the middle of the line dO=dI

25. Use your observations to show where, and then describe how, you would place a MIRA or Reflect-View so that the tip of the arrow always appears to hit the Bulls Eye
Place the Mirror in the middle of the line and rotate it 90° to the line.

26. Use your observations to show where, and then describe how, you would place a MIRA or Reflect-View so that the tip of the arrow always appears to hit the Bulls Eye