1. Working Backwards Task – Hidden Lens

2. A point source will be moved around for you in front of a lens. The lens is hidden behind a screen.

3. Answer the following on your own

4. What type of lens is behind the screen? A. Concave B. Convex C. Cannot be determined

5. Consult with your neighbors and then answer again

6. What type of lens is behind the screen? A. Concave B. Convex C. Cannot be determined

7. A point source will be moved around for you in front of a lens. The lens is hidden behind a screen.

8. Answer the following on your own

9. What type of lens is behind the screen? A. Concave B. Convex C. Cannot be determined

10. Consult with your neighbors and then answer again

11. What type of lens is behind the screen? A. Concave B. Convex C. Cannot be determined