Page 2 - Ta b l e o f C o n t e n ts
Brewster’s Angle Accessory Model No. OS-8170A 2 ®® Ta b l e o f C o n t e n ts Equipment..................................................................................................... 3 Introduction ..................................................................................................
Page 3 - Equipment
® Model No. OS-8170A Brewster’s Angle Accessory 3 ® Brewster’s Angle Accessory Model No. OS-8170A Equipment Included Equipment Model Number 1. Polarizer Assembly (1 lens holder and 2 round polarizers) 003-09784 2. Analyzing Polarizer (1), Lens Mount (1), and Pivot Plate Assembly (1) 003-08332 3. Bea...
Page 5 - Introduction; analyzing polarizer, and a beam splitter.; Theory
® Model No. OS-8170A Brewster’s Angle Accessory 5 ® Introduction The Brewster’s Angle Accessory (OS-8170A) is used in optics for studying the polarization of reflected light and for determining Brewster’s angle. The accessory consists of a lens holder with two polarizers, a rotating platform (Pivot ...
Page 6 - Setup Instructions; Assemble the Spectrophotometer Base
Brewster’s Angle Accessory Model No. OS-8170A 6 ®® where n is the index of refraction of the medium and is the angle of the ray from the normal. When the angle of the incident ray is equal to Brewster's angle, p , n 1 sin P = n 2 sin 2 (2) and since P + 2 = 90 o , 2 = 90 o - P , and sin 2 = sin(90...
Page 7 - Attach the Pivot Plate and Lens Mount; almost; Note
® Model No. OS-8170A Brewster’s Angle Accessory 7 ® 4. Mount a High Sensitivity Light Sensor to an Aperture Bracket and attach the Aperture Bracket/Light Sensor to the Spectrophotometer Arm.) 5. Mount the Rotary Motion Sensor to the upper holes on the hinge of the Spectrophotometer Base. Mount the S...
Page 8 - Align the Laser Beam
Brewster’s Angle Accessory Model No. OS-8170A 8 ®® Align the Laser Beam 1. Put a Laser Diode on the end of the bench opposite to the Spectrophotometer Base.. Connect the laser’s power supply to a grounded electrical outlet and plug the power cord into the laser. Turn on the laser (the ON-OFF switch ...
Page 9 - Controlling the Laser Intensity
® Model No. OS-8170A Brewster’s Angle Accessory 9 ® Controlling the Laser Intensity 1. Place the second optics bench at right angles to the first optics bench at the spot where the Beam Splitter is mounted. 2. Mount the second High Sensitivity Light Sensor on an Aperture Bracket, and attach the Aper...
Page 10 - NOTE; Sensor Setup; Set the Light Sensor Range
Brewster’s Angle Accessory Model No. OS-8170A 10 ®® 8. The square Analyzing Polarizer (see Figure 9) has its transmission axis marked. Position the Analyzing Polarizer with its label on top and with its axis horizontal. NOTE: When the Analyzing Polarizer is horizontal, the light passing through the ...
Page 11 - above; Zero the Rotary Motion Sensor; Procedure; Taking Measurements
® Model No. OS-8170A Brewster’s Angle Accessory 11 ® Note : If the Reflected Light Intensity is as high as possible without exceeding 95%, but the Reference Light Intensity is above 95%, try one of the following to reduce the Reference Light Intensity: • Slightly adjust the second optics bench from ...
Page 12 - horizontal; vertical; Keep
Brewster’s Angle Accessory Model No. OS-8170A 12 ®® 3. Remove the Analyzing Polarizer from the Spectrophotometer Arm. Turn the Lens Mount so that the index mark on the high step is at 85° on the Pivot Plate (measured from the zero mark closest to the Beam Splitter). 4. Rotate the Spectrophotometer A...
Page 13 - Entering the Data; Repeat the Procedure; Analysis
® Model No. OS-8170A Brewster’s Angle Accessory 13 ® Digits display is the same (or close to it). Adjust the Spectrophotometer Arm so the Digits display of Reflected Light Intensity is a maximum. 11. Repeat steps 6 through 9. 12. Continue to repeat the procedure, reducing the angle of the Lens Mount...
Page 14 - Click the “Fit” menu in the toolbar of the Graph; Questions; From the curve fit, how do you determine the minimum of the function?; tan; . What value should you use for n
Brewster’s Angle Accessory Model No. OS-8170A 14 ®® 1. To determine Brewster’s Angle, use the Graph display (“Norm +” versus “Angle”). In the Graph, select a group of data points on both sides of the apparent minimum. 2. Click the “Fit” menu in the toolbar of the Graph and select “Quadratic Fit”. ( ...
Page 15 - Teacher ’s Guide: Discovering Brewster ’s Angle; Sample Data
® Model No. OS-8170A Brewster’s Angle Accessory 15 ® Teacher ’s Guide: Discovering Brewster ’s Angle Sample Data The Table display “Green Data Collection” shows sample data of Angle, Reflected Light Intensity, and Reference Light Intensity for a green (532 nanometer) diode laser.
Page 18 - of polarized glasses? How would you check this?
Brewster’s Angle Accessory Model No. OS-8170A 18 ®® 3. Would Brewster’s Angle be larger or smaller for light in air reflecting off water? The Brewster’s Angle would be smaller for light in air reflecting off water. 4. Would Brewster’s Angle be larger or smaller for light in water reflecting from the...
Page 20 - Further Investigation; II. Intensity of Transmitted Light
Brewster’s Angle Accessory Model No. OS-8170A 20 ®® Further Investigation I. Intensity of reflected light (without polarizer) Note: This experiment uses the same setup except the Analyzing Polarizer is removed and you do not need the second optics bench, aperture bracket, and High Sensitivity Light ...
Page 21 - In DataStudio, set up the displays as shown below.
® Model No. OS-8170A Brewster’s Angle Accessory 21 ® 4. In DataStudio, set up the displays as shown below. 5. Repeat this procedure with the lens turned around. Have the flat side of the “D” lens towards the laser. This will show total internal reflection above angles of about 40 degrees. Sample Dat...
Page 22 - In DataStudio, create the following equations:; Oi; is the incident angle, and; Acknowledgements; American Journal of Physics
Brewster’s Angle Accessory Model No. OS-8170A 22 ®® III. Snell’s Law For the data from the first part of part II, graph Sin (incident angle) vs. Sin (refracted angle). The slope of the line is the refraction index of the acrylic plastic. In DataStudio, create the following equations: a) refracted an...
Page 23 - Appendix A: Creating Equations in DataStudio
® Model No. OS-8170A Brewster’s Angle Accessory 23 ® Appendix A: Creating Equations in DataStudio Step 1: Create a new equation. On the main toolbar, click the Calculate button to open the Calculator dialog. In the Calculator dialog, click the New button. Step 2: Type in and/or build the equation. (...
Page 24 - Appendix B: Laser Safety Information; surroundings, or at the eyes of other individuals.; About Laser Protective Eyewear
Brewster’s Angle Accessory Model No. OS-8170A 24 ®® Appendix B: Laser Safety Information The OS-8525A Laser Diode is a low power, Class 2 laser. When Class 2 lasers are used in accordance with Occupational Health and Safety Administration (OSHA) standards, Class 2 lasers are not harmful. However, wh...
Page 26 - Technical Support; Address: PASCO scientific; Copyright and Warranty Information; Copyright Notice; Brewster’s Angle Accessory Manual; Limited Warranty; Ann Hanks
Brewster’s Angle Accessory Model No. OS-8170A 26 ®® Technical Support For assistance with the OS-8170A Brewster’s Angle Accessory or any other PASCO products, contact PASCO as follows: Address: PASCO scientific 10101 Foothills Blvd. Roseville, CA 95747-7100 Phone: (916) 786-3800 FAX: (916) 786-3292 ...
