1. Light And Optics CPO Science

2. Key Questions  What is light? How can we make light?  Why are there different colors of light?  How does light behave in a prism?

3. Let it glow, let it glow, let it glow  Take white board and keep white side facing up. Don’t look at the bottom!  When I say go, flip board over so white side is down. Place part of a hand over the square. Keep hand there!  When lights go out, remove hand and observe.

4.  Atoms absorb and then emit energy with their electrons  When the energy emitted falls within the visible spectrum we see it as light

5. Charge it up with color  Take out the red, blue, and green LED lights, plug them in, and use them to energize the phosphorescent paper  Remove the colored lights and observe the paper with the room lights off  How can you explain your observations?

6. Light and Color  How does a TV or computer monitor display many, many different colors when they start with only red, blue, and green pixels?  Mix blue and green light. What color do you see?  Mix red and blue light. What color do you see?  Mix red and green light. What color do you see?  Mix all three lights!

8. Overview  Simple Optical System (Beaker Funhouse)  Reflection/Refraction in a Prism (Secret to Tic-Tac-Toe Invincibility and Prismatic Name Enlightenment)  Critical Angle/Total Internal Reflection (Laser Proving Ground)

9. What does Transparent mean?  What happens?  What are some examples of transparent materials?

10. What Is an Optical System?  Anything that involves light  Used to study how light behaves

11. Simple Optical System  Observe the Beaker with the water and pencil in it  Look at the Beaker from many different vantage points  What strange or interesting things can you see involving the image of the pencil?

12. OBSERVATIONS  The pencil is bent  There are two pencils  There are three pencils  The pencil is Magnified  When you look straight down into the beaker, the pencil doesn’t seem bent

13. Color Teaching Tool Slides

15. Refraction/Reflection in a Prism  See Page 112 in the Investigation Guide Handout for written directions  Take out Prism from CPO Optics kit

16. OBSERVATIONS  I can see the X at first  When I move my head up and down the X vanishes  When the X vanishes the O takes its place  This seems to be happening at the same angle, the “magic angle”

17. Prismatic Name Enlightenment  Repeat the process for the X and O but instead of the X write your first name.  Also write your first name in place of the O but this time underline your name.  What information do you now see that can help us explain what is going on?

18. OBSERVATIONS  I can see my name upside-down  When I move my head up and down my name vanishes  When my upside-down name vanishes the underlined name takes its place, and it isn’t upside-down any more  This seems to be happening at the same angle, the “magic angle”

19. Time to Experiment  Use a Simple Model- Laser and Prism  Build Upon What You Have Learned – This Magic Angle is Critical to what is going on

20. Setting Up Laser/Prism Experiment  See Page 113 in the Investigation Guide for written directions  Take out Laser from CPO Optics kit  Use Graph Paper we have provided

21. OBSERVATIONS  The exiting beam exits at a different angle for each trial  When I move the laser up the paper, the exiting beam angles more in the downward direction  At a certain point the exiting beam disappears  This seems to be happening at the same angle, the “magic angle”

22. Conclusions from Experiment  At a certain angle the beam is refracted in a direction that doesn’t exit the prism  This happens at a specific angle-The CRITICAL ANGLE  When the angle is bigger than the CRITICAL ANGLE the beam experiences TOTAL INTERNAL REFLECTION

23. How We Can Use Optics in Everyday Life  Fiber Optics  Laser Scanners  Surgical Lasers  Information Storage-CDs, DVDs  High precision Distance Measuring