Chapter 5, Section 6

1. Chapter 5, Section 6 Reflected Light

2. Date:HW: 5.6 PTG, #1-7, pg. 546, Due • Learning Objective • Explain how light rays are reflected • Describe the relationship between angle of incidence and angle of reflection • Success Criteria • Observe the reflection of light by a mirror • Identify the normal of a plane mirror • Measure angles of incidence and reflection of a plane mirror • Collect evidence for the relationship between the angle of incidence and the angle of reflection for a plane mirror • Observe changes in the reflections of letters • Identify patterns in multiple reflections • Do Now: • Copy LO and SC on a new left side page • WDYS/WDYT pg. 538 • Agenda: • Do Now • Investigate • Summary

3. Investigate • Set up notebook for #1-3 • Complete #1-3, OK with teacher • Set up notebook for #4-6 • Complete #4-6, OK with teacher • Set up notebook for #7-9 • Complete #7-9, OK with teacher

4. Investigate • Set up notebook for #10-12 • Complete 10-12 • Clean up area • OK with teacher

5. Date:HW: 5.6 PTG, #1-7, pg. 546, Due • Learning Objective • Explain how light rays are reflected • Describe the relationship between angle of incidence and angle of reflection • Success Criteria • Observe the reflection of light by a mirror • Identify the normal of a plane mirror • Measure angles of incidence and reflection of a plane mirror • Collect evidence for the relationship between the angle of incidence and the angle of reflection for a plane mirror • Observe changes in the reflections of letters • Identify patterns in multiple reflections • Do Now: • How do you think a mirror works? • Agenda: • Do Now • Investigate • Summary

6. Physics Talk • What are mirrors used for? • To look at your pretty face! • Auto safety • Telescopes • Cameras • CD players • Other technology

7. Physics Talk • What happens when a light ray hits a mirror? • The angle of incidence=angle of reflection • Ray that strikes the surface=incident ray • Ray that is reflects off the surface=reflected ray

8. Physics Talk • Normal line is perpendicular to the mirror • Angle of incidence is between the incident ray and the normal line • Angle of reflection is between the normal line and the reflected ray

9. Physics Talk • What is the Law of Reflection? • Angle of incidence=angle of reflection!!!

10. Physics Talk • What happens to the light rays? • They are reflected off at the same angle they entered • If you extend the reflected rays, where they intersect is where the image appears behind the mirror • The distance from your nose to the mirror is the same as the distance from the mirror to the image in the mirror

11. Physics Talk • Sample problems • Draw in your notebook: • If the angle of incidence is 40°, what is the angle of reflection? • If the angle of incidence increases to 50°, what is the angle of reflection?

12. Physics Talk • Light as waves? • Light is a wave and has properties similar to sound waves • Light waves are transverse waves (motion is perpendicular to the direction of the wave) • Light doesn’t need a medium to travel • Also carry energy (feel warm)

13. Vocab Boxes • Angle of incidence • Angle of reflection • Incident ray • Reflected ray • Normal • Law of reflection

14. Essential Questions • Pg. 545 • What does it mean? • How do you know? • Why should you care?