Refraction of light
A beam of light bends between two media.
Light changes direction when it crosses the boundary between two media. Entering a medium with a higher refractive index, the ray bends toward the normal; entering one with a lower refractive index, it bends away from the normal.
Incidence and refraction angles
There is no refraction angle in the total internal reflection range; the curve ends at the critical angle.
Think about it
When light passes from a medium of higher refractive index into one of lower index, is there always a refracted ray?
Not necessarily. When the angle of incidence exceeds the critical angle arcsin(n₂/n₁), total internal reflection occurs. Try n₁ = 1.5, n₂ = 1 and an angle of incidence of 50°.
Model assumptionsMonochromatic light · angles measured from the normal · dots only indicate direction of travel
Data log
Set the parameters and click “Record data”. Record several rows with different parameters to plot their relationship and fit a straight line; pause and record at different times to study how a reading changes with time.