To calculate the angle of refraction of an incident ray entering a raindrop enter:
- The refractive index of air for a ray with wavelength 589.29 nm. n1) = 1.000293
- The refractive index of water for ray with wavelength 589.29 nm, (n2) = 1.3333
- The Angle of incidence of your ray as it strikes the surface. (θi) = angle between the ray and the normal
The angle of refraction (θ2) will appear in the final box.
Snell’s Law Calculator
https://www.omnicalculator.com/physics/snells-law