1. REVIEW

2. Let’s begin with some review
What are two types of mirrors we talked about?
What property of light allows shadows to form?
Where does an incident ray of light come from?
In a ray diagram, what is a normal?
Why can’t we see things around corners?

3. More Review What is the difference between a Penumbra and Umbra?
What is it called when an electromagnetic wave bends because it travelled from one medium into another?
Why would you want your satellite dish (for watching TV) to be concave in shape, and not convex?

4. Physical Science: Optics
Mirrors, Mirrors, Mirrors

5. Concave mirrors
Concave mirrors are good for collecting light rays into a single point
Light rays will converge to a single point
Called the focal point

6. Concave mirrors Images produced by concave mirrors appear differently:
1. If the object is far away, then the image is small and inverted
2. If the object is between the focal point and the mirror, then the image is larger than the original object, and is upright

7. Diagrams to show how images will be produced

8. Convex mirrors
Convex mirrors are good for reflecting light so they spread far apart. This allows us to see a wider area than normal
Light rays reflect and spread apart. This is described as diverging

9. Convex mirrors
Images produced by convex mirrors have 2 characteristics:
1. Objects appear smaller than they are
2. A wider view can be seen with a convex mirror compared to a plane mirror of same size
Draw diagram

10. YOUR TEST WILL BE A WEEK AND A HALF FROM NOW ON JANUARY 28TH, DAY 4 THIS THURSDAY, JANUARY 22ND, WE WILL HAVE A REVIEW SESSION WRITE DOWN QUESTIONS, BRING THEM TO CLASS. AND ASK THEM!

11. Physical Science: Optics
Concave and convex lenses

12. Concave lenses
Concave lenses are thinner in the middle than at the edges
Light is refracted and diverge apart
Images formed by concave lenses are always smaller and upright

13. Concave lenses

14. Convex lenses
Convex lenses are thicker in the middle than on the edges
Parallel light rays refracts and converges to a focal point

16. Physical Science: Optics
Outcome C3 – Comparing visible light to other types of electromagnetic radiation

17. Review: Electromagnetic radiation
Electromagnetic radiation is the transmission (movement) of energy in the form of waves.
These waves range from long radio waves to very short gamma rays
The electromagnetic spectrum is the range of energies that include long radio waves, microwaves, infrared waves, visible light waves, ultraviolet waves, X-rays and gamma rays.

18. Electromagnetic spectrum

20. TURN TO YOUR PARTNER (TTYP)
Question: Using the figure provided to you, answer:
Wavelengths longer than visible light include?????
30 SECONDS TO THINK OF AN ANSWER WITH YOUR PARTNER
TIME IS UP
15 SECONDS LEFT
Wavelengths shorter than visible light include?????
30 SECONDS TO THINK OF AN ANSWER WITH YOUR PARTNER
TIME IS UP
15 SECONDS LEFT

21. Electromagnetic radiation – WHAT IS IT EVEN GOOD FOR?!
Other types of electromagnetic radiation include:
Radio waves microwaves

22. So what does this all mean?
Long Radio waves - Useful for communication
Microwaves – heats up our food
X-rays – The energy can travel through our skin, but is blocked by our bones

23. Electromagnetic radiation – WHAT IS IT EVEN GOOD FOR?!
Other types of electromagnetic radiation include:
Infrared Ultraviolet

24. Electromagnetic radiation – WHAT IS IT EVEN GOOD FOR?!
Other types of electromagnetic radiation include:
X-rays gamma rays

25. Electromagnetic radiation
How are these different?
TURN TO YOUR PARTNER AND ANSWER:
What 3 differences do specific electromagnetic radiation have from one another… For example: Contrast UV rays to Radiowaves
ONE MINUTE TO THINK OF AN ANSWER WITH YOUR PARTNER
TIME IS UP
30 SECONDS LEFT