PLEASE REVIEW THE INFORMATION BELOW
Reflection and Refraction
Reflection and refraction are two commonly observed optical properties of light. Whenever light strikes the surface of some material at an angle, part of the wave is reflected, and part is transmitted (or absorbed). The reflection of light rays from a plane surface such as a glass plate or a plane mirror is described by the
law of reflection:
Law of reflection
: θi = θr
The angle of incidence (θi) is equal to the angle of reflection (θr).
These angles are measured from a line perpendicular or
normal to the reflecting surface.
Refraction: represents a change of direction that light undergoes when it enters a medium with a different index of refraction from the one through which it has been traveling — for example, when, after moving through air, it passes through water.
Law of Refraction:
n1 sin 𝜃1 = n2 sin 𝜃2
n1 = index of first material
𝜃1 = angle of incidence
n2 = index of second material
𝜃2 = angle of refraction
Procedure
The lab activity uses a simulation developed by the University of Colorado at Colorado Boulder.
Refraction and Reflection Click here
A.
1. Select Material 1 [top Material] is Air
2. Index of Refraction is n1=1
3. Select Material 2 [Bottom Material] is Water
4. Click on Red button,
5. Use protractor and adjust the angel of incidence 𝜃1 = 300
6. Record in the table n2 and 𝜃r and 𝜃2
|
Material 1: Air |
n1 = 1 |
𝜃1 = 300 |
𝜃1 = 300 |
|
Material 2: Water |
n2 = |
𝜃r = |
𝜃2 = |
Q1. What is the happening with the laser beam at the interface between air and water? Are both reflection and refraction laws verified?
B. Repeat steps 1 to 5 but adjust the mediums and angles to the values indicated in the table below.
|
Material 1: Air |
n1 = 1 |
𝜃1 = 300 |
𝜃1 = 300 |
|
Material 2: Glass |
n2 = |
𝜃r = |
𝜃2 = |
Q2. What is the happening with the laser beam at the interface between air and glass? Are both reflection and refraction laws verified?
C. Repeat steps 1 to 5 but adjust the mediums and angles to the values indicated in the table below.
|
Material 1: Air |
n1 = 1 |
𝜃1 = 300 |
𝜃1 = 300 |
|
Material 2: Air |
n2 = |
𝜃r = |
𝜃2 = |
Q3. What is the laser’s beam path?
D. With medium 1- water and medium 2-air slowly increase the incident angle between 300 and 600
Describe what is happening.
What is the name of this phenomenon?
General Physics II, Exp 9: Reflection and Refraction Page 1
General Physics II, Exp 9: Reflection and Refraction Page 1
