What this chapter is about
Light is electromagnetic radiation in the visible spectrum (wavelength ~400-750 nm). It travels in straight lines in uniform media, with a finite speed of ~3 × 10⁸ m/s in vacuum. Ray optics, also called geometric optics, treats light as rays (straight lines) that reflect and refract at boundaries. This approximation is valid when wavelength is much smaller than obstacle sizes. Ray optics explains mirrors, lenses, and optical instruments like telescopes and microscopes.
Understanding ray optics requires knowledge of reflection, refraction, mirrors, lenses, and optical instruments.
Learning objectives
- 1Explain light Propagation, Reflection, Refraction, and Optical Devices
- 2Explain rEFLECTION OF LIGHT
- 3Explain laws of Reflection
- 4Explain types of Reflection
- 5Explain rEFRACTION OF LIGHT
- 6Explain snell's Law
Your learning path
Key terms
Image formationMagnificationTypical valuesAdvantagesSnell's LawAstigmatismConvex mirrorLens equationDisadvantagesCritical angleConcave mirrorDiverging lensMirror equationSign conventionConverging lensRefractive index
Connected chapters
28Concepts
24Formulae
13Minutes