Super Gelatin

Physics and Physical Science
Grade Level

Students measure the angles of refraction of laser light traveling through gelatin, then plot their data to calculate the gelatin’s index of refraction.You may choose from two different "Elaborate" activities:

Gelatin Stack: Students formulate a hypothesis and design a simple experiment to test it.

The “Super” in Super Gelatin: Students calculate how the wavelength and speed of light change inside the gelatin.

Materials You Will Need

Per student lab group

  • Wax paper sheet
  • graph paper (1/4 inch ruled with blue ink)
  • protractor
  • scientific calculator (like a TI-30)
  • Laser pointer
  • binder clip big enough to grip the laser pointer and hold down the “on” switch.

To prepare Gelatin for distribution to lab groups

  •  Knox gelatin (8 x 7 ounce envelopes)
  •  desert gelatin with sugar (like Jell-O®) in red (strawberry) and yellow (pineapple).
  •  cookie sheet (1/2 to 3/4 inch deep, smooth and non-stick surface) or brownie pan (8 x 8inches, 2 inches deep).

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