Physics - Optics - Refraction - Laws of refraction (Snell's law) - Snell's Law of Refraction

A 5-step lesson. Step 1: 'When light passes from one medium to another, it changes speed and (usually) direction. This is REFRACTION. Entering denser medium → bends toward normal. Entering less dense → bends away from normal.' Step 2: 'Snell's Law: n₁ sin(θ₁) = n₂ sin(θ₂). n = refractive index = c/v