3. (10) Record your observations of the change in intensity of unpolarized light after passing through a polarizer from steps 10-11. our observations look same How was it Which mean there's not different, However Whe change the angle from zero to 180. Reduced intensticy, compared suruces Instansity constant, inductor of plarastan 4. (10) Make a conclusion about equation 1 based on your observations from question 3. I = [ o ( 2)5. (10) Record your observations from steps 13-14 in the table below. a. (5) Record your observations from step 6. Intensity of Angle of Angle of Relative First Second Angle Crossed Arrow Between Target Polarization | Polarization Polarization (Min/Max) Axis Axis Axes (9) (9) () max max 0 D Min 9.0 90 b. (5) Record your observations from step 7. Relative Angle of Angle of Intensity of Angle First Second Crossed Arrow Between Polarization |Polarization Target Polarization Axis Axis (Min/Max) Axes min 90 90 0 max 0 max6. (10) Describe how the intensity of the light that passes through the second polarizer changes based on your observations from steps 13-14 of the activity and your answers to question 5. whenin the polaration axes an angled the max . instansity intensity passes through 7. (10) Make a conclusion about Malus's Law based on your answer question 6. I - I. cost8. (10) Record your observations from step 17 of activity. Intensity of Relative Angle Relative Angle Crossed between between Arrow Target Polarization Axis Polarization Axis (Min/Max) 1 and 2 2 and 3 (b) (90' -0) min 90 max 45 45 min 9 0 Oo max 45 45 min 90 9. (10) According to Malus's law, the maximum intensity of light passing through polarizer 3 should have occurred when the relative angle between polarization axes of polarizers 1 and 2, and polarizers 2 and 3, were equal. The minimum intensity should occur when polarization axis of the second polarizer was aligned with the polarization axis of polarizer 1 or 3. Make a conclusion about Malus's law based on your observations from question 8 and the information described in this question. this's constantData Analysis and Conclusions All questions should be answered in complete sentences and in a manner such that the reader does not need to read the question to understand the answer. Answers should be supported with specific data or observations from the experiment when applicable. If there a calculation is required, units should be included on any numerical values that contain them. Failure to follow these instructions on any question can result in up to a 50% deduction in that question. 1. () Record your observations of the light rays from steps 5 and 6 in the table below. dreal ddrawing (cm) (cm) 20.7 21. 2 2. (10) Make a conclusion about how light propagates from a light source based on your observations from question 1. our observations is constantExperiment 9: Malus's Law Objective: After this lab activity, you should understand how light travels from light source. You should understand how the intensity of unpolarized light and polarized light changes after passing through polarizers at different orientations relative to each other. Introduction Light Rays Light rays propagate outward spherically from a light source. At equal distances from a light source, the intensity of the observed light is equal. An electromagnetic wave is polarized along the direction of its oscillating electric field. Unpolarized light, like that from an incandescent light bulb, has a statistically random distribution of every possible polarization. Malus's Law When unpolarized light passes through a linear polarizer, the intensity of the light I decreases by a factor of 2 compared to the original intensity Io. (1) Malus's law states that the measured intensity of polarized light I, after passing through a polarizer, is reduced by the square of the cosine of the angle between the polarization axis of the light and the polarization axis of the polarizer o from its initial value lo. I = 10 cos2 d (2) When light passes through multiple polarizers in a row, the intensity after each polarizer obeys equation 2 taking lo as the intensity of the light before passing through the polarizer. The polarization axis of the light is in the same orientation as the most recent polarizer it passes through. If vertically polarized light passes through a vertically aligned polarizer, the intensity of the light will remain unchanged since cos(0) = 1. If this light then passed through a horizontally aligned polarizer, the intensity of the light would go to zero since cos(90) = 0.Activity Your station should include an optical rail, a light source, 3 component stands, a ray table, a ray table stand, a tray table component stand, 3 linear polarizers with angles, a viewing screen, a slit plate, and a crossed arrow target. Viewing Screen on Slit Plate on Ray Table Component Component Holder Holder Ray Table on Light Ray Stand Source Optical Rail Figure 1. Experimental Setup for Light Rays Portion of Experiment 1. Setup the equipment as shown in Figure 1. There is an AC adapter that powers the light source. 2. Turn on the light source and rotate the knob on the top of the light source until the light bulb inside is centered in the opening. The central beam that passes through the slit plate will align with the 0' mark on the ray table. 3. Fold a piece of paper in half and place the paper on the ray table such that the folded edge of the paper points toward the light source. The edge opposite the folded edge should lie against the viewing screen. Make sure the ray table is close to the slit plate. Mark 6 points on each ray. 4. Unfold the piece of paper. Use a ruler to connect the dots and trace each ray until they converge. If you need a second piece of paper, attach it to the first piece of paper using tape. 5. Measure the distance from the edge of the sheet that was against the viewing screen to the location where the rays converge on the folded sheet. Record your measurement in question 1 of the Data Analysis and Conclusions handout. 6. Measure the distance from the viewing screen to the center of the lightbulb inside of the light source. Record your measurement in question 1 of the Data Analysis and Conclusions handout 7. Remove the ray table and accessories from the optical rail and return them to their place in the optics kit.8. Place the crossed arrow target on the light source. 9. Place a polarizer on a component stand with the 0 mark at the top of the component holder such that the polarization axis is vertical. Place the component stand on the optical rail. The polarizers in the optics kits have polarization axes that are aligned in the direction of the line connected the 0' mark to 180 mark. 10. Observe the intensity of the crossed arrow target through the polarizer compared to the natural intensity of the crossed arrow target. 11. Slowly rotate the polarizer 180, paying attention to any change in the observed intensity as you rotate the polarizer. Record your observations in question 3 of the Data Analysis and Conclusions handout. Polarizer Polarizer Light Source Figure 2. Experimental Setup for Step 5 of Malus's Law Procedure. 12. Rotate the first polarizer back to the 0' mark. The light that passes through the first polarizer with be polarized vertically. Place a second polarizer on a second component stand with the 0' mark at the top of the component holder. Place the second polarizer on the optical rail as shown in Figure 2. 13. Slowly rotate the second polarizer increasing the angle toward 180. Pay attention to how the intensity changes as the relative angle between the polarization axes changes from 0' to 90 to 0' again. Record your observations and the relative angles between the polarization axes in which the observed intensity is minimum or maximum in questions 5a and 6 of the Data Analysis and Conclusions handout. 14. Return the second polarizer to the 0 mark. Slowly rotate the first polarizer increasing the angle toward 180. Pay attention to how the intensity changes as the relative angle between the polarization axes changes from 0 to 90 to 0 again. Record your observations and the relative angles between the polarization axes in which the observed intensity is minimum or maximum in questions 5b and 6 of the Data Analysis and Conclusions handout.Polarizer Polarizer Polarizer Light Source Figure 3. Experimental Setup for Step 9 of Malus's Law Procedure. 15. Rotate the first polarizer back to the 0 mark such that the light that passes through the first polarizer is vertically polarized. Place another polarizer on a third component stand with the 0 mark at the top of the component holder. Setup the three polarizers on the optical rail as shown in Figure 3. 16. Rotate the polarizer 3 to 90 such that the minimum intensity passes through the polarizer when polarizer 2 is removed from the optical rail. 17. Slowly rotate polarizer 2 increasing the angle 180. Pay attention to how the intensity changes as the relative angle between the polarization axes of the polarizer 1 and 2 changes from 0 to 90 to 0' while the relative angle between the polarization axes of polarizer 2 and 3 changes from 90 to 0 to 90 again. Record the relative angles between the polarization axes in which the observed intensity is minimum or maximum in question 8 of the Data Analysis and Conclusions handout