Reflection and Refraction

1. Reflection and Refraction Presented by: Chun Yin Fu Xing Zhong Lin SC442, Honors, Fall 2001, Dr. R.Kezerashvili

2. Objectives • Study and verify the laws of reflection and refraction of light. • Determine the angle of the total internal refraction and the index of refraction

3. Theory • Geometric optics: Light is rays that has straight line of motion, ie. Laser beam. • Physical optics: Light is electromagnetic waves, and wavelength is the main characteristic.

4. Law of Reflection • Angle of incidence equals to angle of reflection: • When angle of incidence changes, the angle of reflection also changes.

5. Law of Refraction • Refraction occurs when light hits two transparent areas. • The angle of refraction depends on index of refraction, n.

6. Law of Refraction • The incident ray, the normal line, and the refracted ray all lie in the same plane. • The relationship between the angle of incidence is determined by Snell’s Law.

7. Critical Angle • The critical angle: during internal refraction, the light that refracted disappeared at an angle. • The angle can be determined by using the index of refraction. n1 and n2

8. Critical Angle • When the angle of incidence is greater than the critical angle, the light is totally reflected at the internal back to the more dense medium.

9. Experiment

10. Experiment

11. Experiment

12. Data

13. Data

14. Data

15. Data

16. Conclusion 1. For flat mirrors, the angle of incidence = the angle of reflection. 2. The angle of refraction depends on the medium used and the angle of incidence. 3. The critical angle is the angle that all the light will reflect back into the denser medium.