Refractive Index Calculator

Calculate refractive index using n = c/v. Compute refractive index from velocity of light in medium, find velocity from refractive index (v = c/n), or calculate speed of light (c = n × v). Features velocity units (m/s, km/s, c), speed of light units (m/s, km/s), and refractive indices for common materials. Perfect for physics and optics students.