Physics

Solve Bragg’s law for d, wavelength, angle, or order. Toggle theta vs 2-theta, pick units, and check if a real solution exists.

Calculate Brewster’s angle from n1 and n2, or solve for a refractive index. Optional Snell’s law check shows the 90 degree relationship.

Convert a glasses prescription to an estimated contact lens power using vertex distance, with cylinder/axis support and optional rounding.

Solve the grating equation for angle, wavelength, spacing, or line density. Includes incidence angle, sign convention, and order feasibility checks.

Convert between diopters and focal length, combine two lens powers, and (optionally) estimate magnifier power with clear sign handling.

Find the horizon distance from your height, with optional refraction and target visibility. Outputs surface and line-of-sight distances.

Calculate refractive index from light speed, or light speed from n. Use Snell’s law mode to solve angles and detect total internal reflection.

Compute laser beam divergence from two spot sizes and distance. Choose full or half angle, units, and compare to a Gaussian limit estimate.

Compute beam diameter and divergence after a beam expander, or solve for magnification or focal length with full vs half-angle controls.