6A40.34 - Index of Refraction - Laser Tape Measure

See paragraph one in the procedure section
Code Number:
Demo Title:
Index of Refraction - Laser Tape Measure
Variable Index of Refraction
Area of Study:
Fish tank with water, Laser Tape Measure, Laminated Note Card.

Position the note card inside the fish tank and at one end.  Make sure 1//2 of it is out of the water and 1/2 of it is under water.  Put the laser tape measure against the outside of the fish tank opposite the note card.  Take distance measurements shooting the laser in air and in water.  The calculated index of refraction from these two measurements should be 1.3 to 1.33.  

NOTE:  The reason this works is because the laser tape measure predicates its measurements on the speed of the laser light though a vacuum.

  • Romulo Ochoa, Richard Fiorillo, Cris Ochoa, "Index of Refraction Measurements Using a Laser Distance Meter", TPT, Vol. 52, # 3, March 2014, p. 167.
  • Frank A. SMith, Jr., "Lecture Hall Calculation of the Refractive Index of a Liquid", AJP, Vol. 47, #1, Jan. 1979, p. 120.

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