Mirage Demo Setup
Curving Laser Beam

 

Code Number: 6A40.40

Demo Title: Refraction - Variable Index of Refraction - Mirage

Condition: Excellent

Principle: Variable Index of Refraction

Area of Study: Optics

Equipment:

Optics tank, laser, jack stands, cork pad, stirring rods, front surface mirror, and sugar water.

Procedure:

Mix up 5 liters of saturated sugar water.  Pour 2 liters of that solution into the bottom of the tank.  With the remainder of the stock make 1500 ml solutions that are 75%, 50%, 25%, and 10% saturated.  Float the cork pad on the 2 liter saturated solution in the tank and pour the 75% saturated solution over the cork pad then repeat this procedure with the other three solutions.  Shine a laser in the flat end of the tank and you should see the laser beam bend toward the bottom of the tank.  For an added effect you may place a front surface mirror at the point where the laser beam hits the bottom of the tank.  This will give you another curved beam reflected outward.  

A variation on this demo is to carefully pour Ethyl Alcohol on top of a layer of water.  In this case the beam will curve upward instead of downward. 

References:

  • John A. Bloom, "Eye-Opening Mirages", TPT, Vol. 60, #2, Feb. 2022, p. 84.
  • Gregory A. DiLisi, "The Sinking of the R.M.S. Titanic: A Case Study in Thermal Inversion and Atmospheric Refraction Phenomena", TPT, Vol. 60, #1, Jan. 2022, p. 11.
  • Front Cover Photo, TPT, Vol. 60, #1, Jan. 2022. p. 1.
  • Yuan Zheng, Zewei Huang, Yanbin Yang, "A Simple Way to Demonstrate and Explain Different Facets of Mirage", TPT, Vol. 59, #6, Sept. 2021, p. 422.
  • Mario Branca, "Simulation of the Inferior Mirage", TPT, Vol. 48, # 9, December. 2010, p. 565.
  • Mario Branca, "Simulation of the Inferior Mirage", TPT, Vol. 48, # 6, Sept. 2010, p. 372.
  • Richard M. Heavers, "Oscillations in a Linearly Stratified Salt Solution", TPT, Vol. 45, # 4, April 2007, p. 241.
  • Paul Gluck, "Material and Optical Densities", TPT, Vol. 45, # 3, March 2007, p. 140.
  • Lauren Richey, Bailey Stewart, Justin Peatross, "Creating and Analyzing a Mirage", TPT, Vol. 44, # 7, Oct. 2006, p. 460.
  • Carl H. Tape, "Aquarium, Computer, and Alaska Range Mirages", TPT, Vol. 38, # 5, May 2000, p. 308. 
  • Se-yuen Mak, "Showing the Light Path of a Mirage", TPT, Vol. 31, # 8, Nov. 1993, p. 476.
  • Jinsong Cui,  "A Demonstration of the Apparent Ellipticity of the Rising or Setting Sun", TPT, Vol. 29, # 9, p. 566, Dec. 1991.
  • J. Wallingford, "More on Mirage Formation", TPT, Vol. 29, # 8, Nov. 1991, p. 485.
  • J.F. Davis and T.B. Greenslade, Jr., "Computer Modeling of Mirage Formation", TPT, Vol. 29, # 1, Jan. 1991, p. 47.
  • William P. Crummett,  "Hard Rock Optics",  TPT, Vol. 24, # 7, p.  414, October 1986.
  • John B. Johnston, "Atmospheric Refraction", TPT, Vol. 42, March 2004, p. 184.  Reprinted from TPT, Vol. 15, # 5, May 1977, p. 308.
  • John B. Johnston, "Atmospheric Refraction", TPT, Vol. 15, # 5, May 1977, p. 308.
  • Anna Horvath, Balazs Bamer, Gergely Gabor Barnafoldi, "Numerical Simulation of Mirages Above Water Bodies", AJP, Vol. 91, #12, Dec. 2023, p. 999.
  • E. Ray, P. Bunton, J. A. Pojman, "Determination of the Diffusion Coefficient Between Corn Syrup and Distilled Water Using a Digital Camera", AJP, Vol. 75, # 10, p. 903, Oct. 2007.
  • C. Gaffney, Cheuk-Kin Chau, "Using Refractive Index Gradients to Measure Diffusivity Between Liquids", AJP, Vol. 69, # 7, p. 821, July 2001.
  • Waldemar H. Lehn, "Exact Temperature Profile for the Hillingar Mirage", AJP, Vol. 69, # 5, May 2001, p. 598.
  • T. Kosa, P. Palffy-Muhoray, "Mirage Mirror on the Wall", AJP, Vol. 68, # 12, December 2000, p. 1120.
  • P. R. Barker et al,  "A Superior "Superior" Mirage",  AJP, p. 953, Vol. 57, No. 10, October 1989.
  • Kevin M. Jones, Scott Lundgren, and Alak Chakravorty, "A Calculus of Variations Demonstration: The Gradient Index Lens", AJP, Vol. 56, #12, Dec. 1988, p. 1099.
  • George Spagna, "Laser Beam Deflection by Thermal Gradient", AJP, Vol. 51, #5, May 1983, p. 475.
  • K. Tennakone, "A Mirage From a Laser", AJP, Vol. 51, #3, Mar. 1983, p. 270.
  • E. Fabri, G. Floria, F. Lazzeri, P. Violino, "Mirage in the Laboratory", AJP, Vol. 50, # 6, June 1982, p. 517.
  • M.M. Michaelis, "Laser Beam Guidance by Flames", AJP, Vol. 48, # 11, November 1980, p. 990.
  • G. P. Sastry, "Teaching Mirages", AJP, Vol. 46, #7, July 1978, p. 765.
  • P. L. Dyson, "Comment on Explaining the Mirage", AJP, Vol. 45, #9, Sept. 1977, p. 879.
  • E. Khular, K. Thyagarajan, and A. K. Ghatak, "A Note on Mirage Formation", AJP, Vol. 45, #1, Jan. 1977, p. 90.
  • A. J. Barnard, B. Ahlborn, "Measurement of Refractive Index Gradient By Deflection of A Laser Beam", AJP, Vol. 43, # 7, July 1975, p. 573.
  • Robert T. Bush, Robert S. Robinson, "A Note on Explaining the Mirage", AJP, Vol. 42, # 9, September 1974, p. 774.
  • William M. Strouse, "Bouncing Light Beam",  AJP, Vol. 40, # 6, June  1972, p. 913.
  • Giuseppe Poggi and Carlo Pontiggia, "The Mirage in The Lab", AJP, Vol. 37, #3, Mar. 1969, p. 332.
  • Robert Ehrlich, "10.8: Mirage Formation", Why Toast Lands Jelly-Side Down, p.164.
  • T. Kallard, "Curving and Bouncing Laser Beam", Exploring Laser Light, p. 58.
  • Pat Murphy, Ellen Macaulay, and the staff of the Exploratorium, "Disappearing Puddles", Exploratopia, p. 289.
  • Carl. H. Tape, "Aquarium, Computer, and Alaska Range Mirages", TPT, Vol. 38, # 5, May 2000, p. 308.
  • M. Minnaert, "IV, The Curvature of Light Rays in the Atmosphere", Nature of Light and Colour in the Open Air, p. 39.
  • Jearl Walker,  "Bouncing a Light Beam",  The Flying Circus of Physics with Answers, p. 119.
  • C. Harvey Palmer, "A Note on the Properties of Inhomogeneous Media",  Optics - Experiments and Demonstrations, John Hopkins Press, 1962.
  • Tik L. Liem, "The Reflecting Brick Wall", Invitations to Science Inquiry - Supplement to 1st and 2nd Ed. p. 93.
  • Julius Sumner Miller, Q14 & A14, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 21 & 80.