Refraction
Physics · अपवर्तन · 16 facts
Refraction: light bending passing from one medium to another
Light bends toward normal (rarer to denser); away (denser to rarer)
Snell Law: n1.sin(i) = n2.sin(r)
Refractive index = speed in vacuum / speed in medium
Diamond n=2.42, glass=1.5, water=1.33, air=1.0003
Diamond sparkles: high refractive index + total internal reflection
TIR: incidence angle > critical angle in denser medium
TIR uses: optical fibre, mirage, diamond, endoscope
Mirage on hot road: TIR creates water illusion
Lens formula: 1/v - 1/u = 1/f; Power = 1/f Dioptre
Convex lens: corrects hypermetropia (far-sightedness)
Concave lens: corrects myopia (near-sightedness)
Pencil in water appears bent (refraction at boundary)
Stars twinkle due to atmospheric refraction
Prism disperses white light into VIBGYOR; Newton discovered
Pool appears shallower than actual depth (refraction)