Refraction Index- Invisibility (Mary Eckel)

Author

Mary Eckel

Principle(s) Illustrated

1. Describes the change of direction of a light wave when the wave moves from one medium (corn oil) to another medium (air).

Standards

• Physics 4f. Students know how to identify the characteristic properties of waves: interference (beats), diffraction, refraction, Doppler effect, and polarization.

Questioning Script

Prior knowledge & experience:

Light moves in waves.

The direction of the wave can change based in the medium it is traveling through.

Root question:

Why does the test tube disappear?

Target response

The refraction index is the same for the "magic liquid" (corn oil) and the pyrex glassware.

Common Misconceptions:

The liquid is the same color, that is why the test tube seems to disappear.

The test tube disappears because there is corn oil inside.

Photographs and Movies

References

Disappearing Test Tube