#Reflection and Refraction on the basis of wave theory #wave optics#class12

#Reflection and Refraction on the basis of wave theory #wave optics#class12 ⭐ Reflection and Refraction on the Basis of Wave Theory – YouTube Description In this video, we explain Reflection and Refraction of Light using the Wave Theory proposed by Christiaan Huygens. According to wave theory, light travels in the form of waves, and every point on a wavefront acts as a source of secondary wavelets. Using this idea, we can beautifully understand both reflection and refraction. 🔵 Reflection (Wave Theory Explanation) When a wavefront strikes a smooth reflecting surface, each point on the surface becomes a source of secondary wavelets. These wavelets spread out and form a new reflected wavefront. From this construction, we get the laws of reflection naturally: 1️⃣ The angle of incidence equals the angle of reflection. 2️⃣ The incident wavefront, reflected wavefront, and the surface all lie in the same plane. Thus, wave theory proves why light bends back in a predictable manner on a reflecting surface. 🔵 Refraction (Wave Theory Explanation) Refraction occurs when light passes from one medium to another — like air to water. According to wave theory, the speed of light changes when it enters a new medium. Because of this change in speed, the secondary wavelets in the new medium form a refracted wavefront that is bent at an angle. From this construction, we understand that: Light bends towards the normal when it slows down (denser medium). Light bends away from the normal when it speeds up (rarer medium). And Snell’s Law (n₁ sin i = n₂ sin r) is directly obtained from wavefront geometry. 🔵 Why Wave Theory Is Important Huygens’ principle not only explains reflection and refraction but also gives deep insight into how light behaves as a wave. It forms the foundation for wave optics, interference, diffraction, and polarization.