6A44.25 • Total Internal Reflection: Snell’s Wheel

Location: Floor Demo

Photo Shows the Demonstration Apparatus Used by the University with the room lights dimmed. of Texas at Austin.

Instructions / Notes:

• A laser beam pointed at a Snell's wheel which be used to demonstrate refraction and total internal reflection.
• Rotate the wheel to determine the critical angle for total internal reflection.

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Demo Staff:

• Check the alignment of the laser beam through the Snell's wheel before the start of each class.
• Adjust alignment by rotating the laser along the horizontal plane.
• The lasers in the demo are quite dim, so make sure that the professor is aware of this fact.

Photo Shows the Demonstration Apparatus in Use with the room lights still on.

Last updated on June 22, 2026