how to get refractive index of liquids using laser pointer.

1. Department of Physical Sciences Faculty of Science and Technology Universiti Malaysia Terengganu (UMT) 2006 STUDY AND VISUALIZE THE CONCENTRATION DEPENDENCE OF REFRACTIVE INDEX OF THE LIQUIDS NORENAFIDAH BINTI MAT TARMIDI UK10775 Bc. of Applied Science (Physics Electronics & Instrumentation)

2. outline INTRODUCTION REFERENCES METHODOLOGY RESULTS & DISCUSSION CONCLUSIONS ACKNOWLEDGEMENTS ABSTRACT

3. ABSTRACT

4. Laser based measurement have been found in early 1900 indirectly by Albert Einstein during the research of photoelectric effects and until now, its application still growth. The main objective in this project is to study the dependence of refractive index (RI) on the concentration by laser based measurement. Low power laser pointer with the output of 1mW and the wavelength of 630 to 670nm are employed as a light source. The phenomenon of refraction occurs when a monochromatic laser light source passed through the prism which full with liquids. In this study two types of liquids consist of sugar and salt solution were utilized as a sample. Generally, refraction happened when the source light travel through two different medium like air and sugar water because of the slightly change of speed of light. Hence, the output of light from the second medium were refracted far away from the normal line and it is called the index of refraction, n where can be determined by using Snell’s. The concentration of these liquids were carried is from 5% to 65%. The RI value for both sample are proportional with its concentrations. The experimental value than has been compared with literature value. The differences are 1.5% for sugar and 5% for salt. Then, based on our experimental set up, we developed an interactive ‘Easy_GUI’ language to determine the RI value for the future accessibility.

5. CHAPTER I INTRODUCTION

6. Used LASER POINTER Produced REFRACTION PHENOMENA Calculated REFRACTIVE INDEX Developed Graphical User Interface (GUI) ‘ Easy_GUI’

7. Coherence beam Not too dangerous Low-cost material and money Small and easy to use Monochromatic source

8. OBJECTIVES

10. CHAPTER II METHODOLOGY

13. Point a Point b X L Figure 2.1. The laser light hit the prism which full with solution sample. 102 cm Point d Point e Point c 2.3 Experimental Set up

14. 2.4 Create Programming of GUI Property Inspector Run button Click Matlab 7 software. Write the ‘guide’ & press enter at the command window. Click ‘ok’ at the quick guide start. Layout editor of GUI appear.

16. t = get(handles.edit1, ‘String’); s = ‘2.0005*sin(0.5*(t + 1.047))’ set(handles.edit1,‘String’,s)

17. chapter iii results & discussion

18. Table 3.1: The average percentage concentration of refractive index for sugar solution. 1.4251 30.8546 73.82 44.10 65% 1.3999 28.8121 77.05 42.38 50% 1.3799 27.2193 79.93 41.11 35% 1.3513 24.9751 84.04 39.12 20% 1.3397 24.2845 84.99 37.99 5% RI ( n )  md L (x10 -2 ) cm X (x10 -2 ) cm Concentration (%)

19. Figure 3.1. The exponential graph of refractive index proportional with its concentration.

20. Figure 3.2. The Refractive index of sugar solution as a function of its concentration percentage.

21. Table 3.3: The average percentage concentration of refractive index for salt solution. 1.5227 39.1368 71.14 57.90 65% 1.4785 35.3122 80.98 57.42 50% 1.4708 34.6455 75.75 52.34 35% 1.4051 29.2292 83.82 46.90 20% 1.3523 25.0602 83.92 39.24 5% RI ( n )  md L (x10 -2 ) cm X (x10 -2 ) cm Concentration (%)

22. Figure 3.3. The RI with its percentage concentration for salt solution.

23. Figure 3.4. Comparison of salt and sugar solution in constant percentage of concentration.

24. Table 4.2: The comparison value of experimental value for present technique and literature value from Albrecht, (2003), Subedi et al , (2006) for sugar solution. Figure 3.5. RI versus the percentage concentration of sugar solution. 9.9 1.435 1.4251 65 11.1 1.411 1.3999 50 3.1 1.383 1.3799 35 5.7 1.357 1.3513 20 2.3 1.342 1.3397 5 Different value (x10 -3 ) Literature value Experimental value Concentration (%)

25. Table 4.4: The comparison value of experimental value for present technique and literature value (salt solution). Figure 3.6. The experimental RI value of salt solution times its concentration in percentage with the literature value. 21.3 1.544 1.5227 65 23.5 1.502 1.4785 50 38.8 1.432 1.4708 35 37.1 1.368 1.4051 20 10.3 1.342 1.3523 5 Different value Literature value Experimental value Concentration (%)

26. Figure 3.7. The ‘Easy_GUI’ box for measure the RI of the liquids.

27. Figure 3.8. The graph of RI versus the minimum angle of deviation when the value of RI insert in the equation. 1.34214

28. chapter v conclusions

31. references

32. Albrecht, J. 2003. The Refractive Indexs of The Liquids. Optics. Vol. 3, 3 rd ed. United State. Abdulla, A.I. 2004. Introduction to Graphical User Interface (GUI) MATLAB 6.5. Electrical Engineering Department, IEEE UAEU student branch, UAE University College of engineering. Catherasoo, C.J. & Sturtevant, B. 1983. Shock dynamics in non-uniform media. Journal of Fluid Mechanics 127:539-561. Cap, N., Ruiz, B., & Rabal. H. 2003. Refraction holodiagrams and Snell’s law Optics 114(2):89–94. Chien, D.N., Tanaka, K. & Tanaka, M. 2003. Guided wave equivalents of Snell’s and Brewster’s Laws. Optics Communications 225:319–329. Chauvat, D., Bonnet, C., Dunseath, K. Floch, A.L. & Emile, O. 2005. Timing the total reflection of light. Physics Letters A 336:271–273. Davis, J. & Xing, C. 2002. Lumipoint: multi-user laser-based interaction on large tiled displays. Displays . 23:205-211. Subedi, D.P., Adikari, D.R., Joshi, U.M., Poudel, H.N. & Niraula, B. 2006. Study of Temperature and concentration dependence of refractive index of liquids using a novel technique. Department of Natural Sciences, Khatamandu University, Nepal.

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35. Q & A SECTION