Solve this:

Solve this: 5:25 PM Question 25 (2/2) Mark: 5 0 e State Huygens' principle. Using the geometrical construction of secondary wavelets, explain the refraction of a plane wavefront incident at a plane surface. Hence verify SnelFs law of refraction. Illustrate With the help of diagrams the action of (l) convex lens and (li) concave mirror on a plane wavefront incident on it. Solution Every point on the given wavefront acts as a fresh source of new disturbance, called secondary wavelet, which travel in all directions with the velocity of light. A surface, touching these secondary wavelets tangentially in the forward direction at any instant (or forming the envelop of these secondary wavelets) gives new wavefront at that instant Medium I p Medium 2