The Refractive Index
Part of the Optics, Waves and Modern Physics section of Coddy's Physics journey. Lesson 2 of 53.
Light is slower in water and glass. The refractive index says how many times:
n = c / v
Air 1, water 1.33, glass about 1.5, diamond 2.42. n is never less than 1.
Into a slower material: toward the normal. Into a faster one: away from it.
Challenge
Light travels through a glass at 2 × 10⁸ m/s. What is the refractive index n of this glass?
Try it yourself
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Optics, Waves and Modern Physics
1Reflection and Refraction
Reflection of LightThe Refractive IndexSnell's LawTotal Internal ReflectionDispersionApparent DepthRecap - Optical Fiber4Mechanical Waves
What a Wave IsTwo Graphs of a WaveWhen Pulses MeetInterferenceStanding WavesHarmonicsRecap - Guitar String