| Quantity | Value |
|---|
Snell holds for rays at a smooth interface between two homogeneous media. Total internal reflection needs light going from a higher index to a lower one AND an angle past the critical value — from low to high there is no critical angle and no TIR. Fresnel here is for a lossless interface at normal-ish conditions; real surfaces add absorption, so T = 1 − R understates what a coloured or absorbing medium transmits. These are the textbook indices, not wavelength- and temperature-dependent measured ones.
Independent, paired and one-sample t-tests from real summary statistics: the t statistic, degrees of freedom, p-value and a verdict at alpha 0.05.
Push uncertainties through any formula step by step, in quadrature or worst case, with partial derivatives and a relative or absolute output error.
Length, area and volume change with temperature for any material, plus the fixed-length gap a joint needs to stay sealed from cold to hot.
Add or subtract business days with a real holiday calendar, count working days between two dates, and see every excluded weekend or holiday listed.
Translate text to Morse and back with audio playback.
Title, AP, Chicago, sentence, camel, snake and kebab in one tool.
Remove all HTML tags and decode entities to plain text.
Convert plain text to HTML paragraphs with escaping and headings.
