Measure the Index · TheLucidSTEM

Interactive Simulator · Measure the Index

Refractive Index

The refractive index n measures how strongly a material bends light: it is the sine of the angle in air divided by the sine of the angle in the material. A higher index bends light more and means light travels more slowly inside, since n = c divided by the speed in the material. For one material n stays the same at every angle. Pick a material and set the angle of incidence to reach the target angle inside it.

Mission Refract the ray to 20° from the normal inside the material. Round 1Streak 0Best 0

Angle of incidence 45°

A material with a higher refractive index bends light:

materialglass

angle in air / in material45° / 28°

n = sin i ÷ sin r1.50

speed inside (c ÷ n)2.0 ×10⁸ m/s

n is the same at every angle for a given material.